Change in the Air

A number of changes to talk about in the coming weeks, and a time to look at the state of things as this school year approaches an end.

First the changes. It looks like I will not be teaching Regents Living Environment at my current school next year. That can be interpreted in a couple of different ways, and I will leave it ambiguous for the moment. That also leaves open the question of whether this blog becomes obsolete next year - or at least the title.

The second change is that I am looking for an alternative hosting set-up for my website. I currently use Hostway, which has been excellent - I can't remember a single moment of down time - but I can't afford it any more, and I'm looking for a number of ways to cut back on expenses. I started with hostway back when I was setting up the website as a staff developer for District Six in NYC, and the district picked up the tab. I'm looking for reliable cheap alternative hosting, but I may have to settle for cheap. I'm looking at Globat, which has some special offers from gotapex. All this means that there may be some down time as I make the switch.

End of year issues. I'm in full regents prep mode as panic sets in. Of course students are getting less & less focused on school because that's just what happens in middle school - Most students have no more real exams left. The 8th grade science & social studies tests are jokes in the sense that there are no consequences for students or schools if the students don't perform well, so there's little pressure on anyone to take them seriously. So here I am asking them for the first time in their lives to be serious all the way to June 22nd when the Regents exam is scheduled. They know that they will be in school with me reviewing for an exam even when most of their classmates are finished ("graduation" is June 16th).

My colleague (who teaches one regents class) and I will begin extra tutoring sessions next week for students in danger of failing the exam. I'm giving my final practice exam this week to gauge who needs the most help. I'm hoping that only 15-20 kids (out of 60) will require extra help. As I've stated before, because we are an 8th grade program, I want everyone to get 75 or better on the exam so there won't be any hassles with their high schools because they barely passed. I know that all students at 75 or better is probably unrealistic at this point, but it's still a goal.

Still left to cover. Student exit projects are due next Friday. I've been helping them along with the different parts of the written report, and will post a few when they are done. I will also post some of my strategies for getting the written part completed. In short, they will hand in different elements of the report each day between now & next Friday (I don't have any revolutionary fool-proof methods here). This will allow me to give them feedback pretty quickly for editing. By Friday they will have to fix any problems and put it all together.

I still have some ecology concepts to cover. Most of the basics were taught last year, so I don't have to do a full ecology unit. Just review and elaborate. I will need to do a lab on plants along with photosynthesis/respiration.

I need to review evolution and particulary human evolution. That will have to be a quick powerpoint presentation, unfortunately. Ditto for biotechnology.

Finally, I need to do 3 more required labs. It sounds like a lot, but I do get 8 periods per week (minus some days for end-of-year nonsense). Also, most of the basic ideas in the required labs have already been covered to an extent in other labs. If I teach LE again next year, I will know much more about time management than I did this year. I spent too much time on some topics (relative to their importance in the exam) and too little on others.

Student Blogs Revisited - Again

I haven't quite given up on student blogs, but I am going back to a modified version of my original plan, which was to have a single blog for an entire class, with students now contributing the posts instead of me posting assignments and asking students to respond in the comments section.

I probably should have anticipated the difficulty in monitoring several student blogs at one time, but I was overly ambitious and optimistic, as usual. What's that line about people repeatedly doing the same thing over and over and expecting different results? (Definition of insanity).

I am a little surprised that students didn't take some initiative on their own - after all, I made it acceptable to write about things other than science on their blogs, but all I got was a few students doing a couple of posts for extra credit, then basically abandoning their blogs.

So I will link again to the original Class Blogs - 801 & 807 - and Monday will give students assignments to post their ideas for extra credit.

Exit Project Questions

I promised (long ago) to post some of the projects that my students are working on. I repeat that I needed projects with relatively short data collection times, since my top priority is preparing for the Regents Exam. I was not concerned with students coming up with elaborate or novel ideas, and am more concerned that they do a thorough job with a simple idea and be able to explain their results at a pretty sophisticated level. I gave them a deadline of May 6th to finish with data collection, anticipating another week or so to process the data, write up their results, and present their findings. I have donated class time - a double lab period once per week - and have made myself available to them after school if they need extra time or help. So, here are a few more projects that my students are doing, written as problem questions, with descriptions following the questions.

How does temperature/pH/detergent concentration affect enzyme action?


A follow up on the lab we did called mello jello. Enzyme action is measured by the increased diameter of a well cut out of a jello sample, filled with detergent solution. The original lab looked at various detergents, students' projects manipulated one of the other variables listed in the title - in other words, three different experiments/projects came out of this lab.

How do different foods affect mealworm growth?


Student has three containers with 20 mealworms each, records mealworm growth(measured in grams) after several weeks. Student also keeps track of molting to the extent possible and metamorphosis where applicable. Student will be expected to explain results based on some measurable quality of the foods involved - caloric content, texture, moisture content, etc.

How does weight affect heart rate?



Students are taking measurements of subjects at rest, walking, and running short distances and correlating with weight/height, body-mass index.

How does height affect speed?



Students are testing subjects of various heights and looking for correlations with time it takes to run a certain distance.

--A lot of seed germination projects - temperature, salt content, light exposure, size of seed.

How do different concentrations of detergent affect DNA extraction from wheat germ?



A variation on the lab we did on DNA extraction. Using protocol, altering only one variable in the procedure. Student will extract DNA, dry on filter paper, weigh the results.

NOTE: I purchased some inexpensive twin beam balances that measure to 0.01 gram precision.

How does the mass of a lemon affect the voltage produced by a "lemon battery?"



OK, so they are actually using oranges for some reason. Pretty self-explanatory. My only comment is that they somehow have to look at this more from a biological perspective rather than physical science, but of course the distinction is rather artificial in the end. What I means is, what does the lemon battery have to do with the functioning of living things?

That's enough for now. For anyone reading these titles after searching for science fair projects, I would only point out that each of these projects, as I constantly stress, has a measurable dependent variable and each is looking for a cause and effect relationship, or at least a correlation between two variables. The New York City Exit project requirement states that all projects should follow this model, whether it is a controlled experiment, a field study, or a secondary research project. Even design projects should include a controlled experiment to test some aspect of the design. You can check out the old District Six Project Guidelines for a more complete discussion of these different projects.

Dog Days

After stepping in dog crap yesterday during my evening jog across the George Washington Bridge*, I thought this an apt title for how I'm feeling right now about regents biology in grade 8.

I'm playing content catch-up. Rushing through body systems with the dreaded lecture-textbook-quiz drill that I so despise, but seeing little alternative at this late stage of the game. I will definitely need to work on pace & sequence and all that next year.

If you have to lecture...

I'm using a lot of power-point presentations, which I find infinitely preferable to writing on the chalkboard and having students flip through the book for pictures. For some reason, students seem more engaged - most likely because I don't have to divert my attention from the class while writing on the board, so I can monitor them almost constantly. More importantly, the pictures often precede the text, so I can engage them with the pictures, ask them to make predictions or recall information based on prior knowledge, and introduce the text as we go along - again, without turning my back or giving them the excuse that they are waiting for me to get out of the way so they can write the notes (with all the opportunity there to lose focus). Ms. Frizzle had a post recently defending the use of powerpoint presentations - I didn't know there was even a controversy. I prefer not to lecture, but if one must, then powerpoint is the way to go with this age group.

What about the time it takes to prepare a powerpoint presentation? I cheat. A lot of powerpoints can be found on the web, and I just edit them for my own purposes. For that reason, I won't be posting my presentations, at least for now. But I do use a lot from Mr. Kolakowski's website - he's a regents LE teacher in upstate NY.

On the other side, we are still working on exit projects, for which I give them our Monday double periods. I will post separately on this subject later. I also have to get the remaining required state labs in, but I'm in no rush on that. I will post my thoughts on those labs as we do them.

*I was transitioning from bright sunlight to dark shadows and couldn't see the stuff, even looking back after I realized what that squishy feeling was under my left foot. I'm always hyper-vigilant about dog crap in this stinking neighborhood and it still found my foot. Do I sound a little (pet-) peeved? I am.

NYC DOE - Grow UP!

I just googled "excretory system" at school on the Department of Education server, and got this familiar message:

Access Denied

The requested document, http://www.google.com/search?hl=en&q=excretory system&btnG=Google Search, will not be shown.

Reason: DDR score = 139. This page will not be displayed because it contains prohibited words or it has exceeded its tolerance of questionable words.

I've seen this a lot when trying to navigate to a particular site or page of a site - a lot of legitimate science content is off limits using the DOE filters - , but this is a first. I can't wait to get home and see what google returned about the excretory system that is so offensive they can't even show the search results!

Later that day...

So here are the results of my search:

Excretory System
... Excretory System Functions Invertebrate Excretory Organs Vertebrates ...
The Human Excretory System Kidney Function Hormone Control of Water and ...
www.emc.maricopa.edu/faculty/ farabee/BIOBK/BioBookEXCRET.html - 24k - Cached - Similar pages

Pathfinders for Kids: The Excretory System - The Garbage Collector
This pathfinder is a guide to help kids find information about the excretory system.
infozone.imcpl.org/kids_kidny.htm - 11k - Cached - Similar pages

Excretion
... You would probably figure out a system of searching and removing. That would
be an excretory system. Your body does the same thing every day. ...
sln.fi.edu/biosci/systems/excretion.html - 8k - Cached - Similar pages

Human Excretory System
... Its numerous functions make it "part" of the circulatory, digestive, and
excretory systems. ... There you have it, the Human Excretory System. ...
www.borg.com/~lubehawk/hexcrsys.htm - 53k - Cached - Similar pages

Excretory System
... Some diseases and disorders of the excretory system include:. Nephritis is an
inflammation of the glomeruli, due to a number of possible causes, ...
biology.clc.uc.edu/courses/bio105/kidney.htm - 26k - Cached - Similar pages

Excretory System
EXCRETORY SYSTEM. OVERVIEW :. On this page you will learn about the Excretory
System, which removes the unwanted materials from our body. ...
library.thinkquest.org/ 10348/find/content/excretory.html - 6k - Cached - Similar pages

Excretory System
The job of the excretory system is to remove various produced by the body.
The removal is known as excreation. It is important for the body to remove these ...
www.stclement.pvt.k12.il.us/ StudentWeb/science/excretionc/excsyst.htm - 2k - Cached - Similar pages

Excretory System
Chapter 42 - Excretory System. Function of the Excretory System. The excretory
system functions in ridding the body of nitrogenous (nitrogen-containing, ...
faculty.clintoncc.suny.edu/.../files/Bio%20102/ Bio%20102%20lectures/Excretory%20System/excretor.htm - 21k - Cached - Similar pages

Excretory System
... Endocrine System Circulatory System Lymphatic and Immune System Digestive
System Excretory System Muscle and Skeletal System Respiratory and Skin System ...
www.scientia.org/cadonline/Biology/excretory/home.ASP - 3k - Cached - Similar pages

The Excretory System
... Nitrogen Wastes ..The Human Excretory System ..Water and Salt Balance . ...
Excretory System Functions ..Hormone Control of Water and Salt . ...
www.cartage.org.lb/en/themes/Sciences/LifeScience/ GeneralBiology/Physiology/ExcretorySystem/mainpage.htm - 5k - Cached - Similar pages

OK? So where are the questionable or objectionable words? The only questionable word I see is the misspelling of excretion - excreation in the 7th entry.

I realize there are ways around the word "excretion" and had no trouble with "kidneys" for example, but really, the DOE security settings are a joke.

And don't even get me started on the restriction on accessing the sports websites or even an article on sports from the NY Times. Some of the girls in my class sit around (before or after school starts) drooling over the Gotti boys and the DOE security system has no problem with that. But let someone try to read a sports page and whoa, hold on there, sorry, DOE don't allow sports over our internet servers!. I can't think of any legitimate use of celebrity gossip crap, but there's no restriction on it. I can think of plenty of uses for sports - statistics, secondary research, social studies connections, etc., but kids can't access any sports info on the DOE servers. Gimme a break.

Exit Projects in Full Swing

The dilemma, of course, is that my primary focus this year is getting my students to pass the regents exam, and as I've stated ad nauseam before, I'm a little nervous about it, having no prior experience in teaching the curriculum and little or no support from the state of New York (as in the New York State Regents Living Environment Exam).(1) On the other hand, grade 8 students are supposed to also complete an 'exit project" which I have likewise discussed in earlier posts. To guide students properly through a year-long exit project is just a bit more than I can handle, so we are doing pared down projects that are really just getting started and are due on May 6th, at least as far as the students are concerned. In reality, I want all their research and data collection completed by May 6th, and if we take a little longer to get everything written up properly and presented, then maybe closer to May 20th for the final due date.

Most students are doing fairly simple projects - a good number of the old stand-by germination experiments, plant growth experiments, etc. Some students are taking my advice and reworking some of the experiments we already did in class (gelatin-detergent lab, e.g.), others are sticking with their secondary research projects on genetic diseases. What I expect from my regents classes is a solid experimental design, an extensive set of data, and a thorough understanding of the biology concepts to explain the data. I am giving them Mondays during class to work on projects as we continue with some pretty old-school lessons on human biology the rest of the week. Any other time they need will have to be after school. I will be collecting their experimental design diagrams later this week and post some specific examples, discussing how my expectations are different from what I've seen in similar other projects. Such as:

One group is investigating how salt affects plant growth. A pretty standard middle school science fair project, not very imaginative, not that exciting. Mostly this is done with a control group, a group that gets maybe a 5% salt solution, and a third group that gets a 10% salt solution, e.g. The 10% usually dies or doesn't grow at all, the 5% maybe lives but looks pretty sickly, and the control group does just fine. End of experiment. At this level, however, that would be a starting point. Now the challenge will be to go back and re-do the experiment with concentrations of salt between 0 - 5%, challenge them to find ANY concentration of salt that does not negatively affect plant growth. There are of course other directions the investigation could lead, such as looking for plants that are more resistant to salt, for example, but under the circumstances we will stay with the salt concentrations. Students will then have to discuss the physiological effect of salt on the plants. Why does salt harm the plants, maybe describe the role of salt in our own bodies, etc. You get the idea.

(1)References to curriculum matters here and here.

UPDATE

I neglected to mention that a sizeable chunk of the regents exams is related to understanding experimental design and the scientific process, so I realize that having students work on these projects is not taking away time that we need to prepare for the exam, it IS preparing for an important part of the exam. I am still struggling on the whole with how to integrate content & process over the long haul - I can do it in short bursts of activity, but putting it all together for a coherent year-long sequence of instruction is not easy.

Dissection

Sheep Hearts. Our first real dissection of the year. We have boxes of these things in the supply room, left over from the Insights Human Body Systems kits that are supposed to be used in grade 6. For whatever reason, the sheep hearts lie there unused, many teachers will either do a dissection as a demo, or avoid it alltogether, so we have a surplus.

I didn't take any pictures but there are a few on the internet that I will link here in case you wind up here:

Sheep Heart - Labeled

I used a simple checklist for students to document their work and they had to sketch their observations as well. I got the worksheet off the web, but I've lost the link - I'll search for it later and post as an update.

The kids love this stuff, for the most part, but I wish the dissections could be richer. I would like for them to be able to measure something, make comparisons, but I could neither find nor think of any angle.

Update

I accidentally hit the publish button before I was finished, it being now a Saturday night and I'm composing this post during time-outs in the Final Four games.

I'm thinking of some possible measurements for the frog dissections that we wll do in a couple of weeks. I'll post more as I work out the details.

Back to Basics?

After going through a series of labs and projects over the last few weeks, I looked at the calendar and the curriculum and started to panic. Actually, the panic began when we spent 2 weeks on a digestive system project and got disappointing results on the regents test items relating to digestion. Now I am looking at a good deal of content that still needs to be covered, wondering how I can fit it all in. I've got most of the human bio topics still to address, plus ecology. I need to revisit evolution and genetics in the ecology unit and genetic engineering in the human bio section. That's about one calendar month for each of those major sections, then a couple weeks for regents review in June. That means any labs or projects we do need to be pretty tightly connected to the curriculum, limited in focus, and held to a pretty tight schedule. Looks like a lot of planning & thinking this weekend about how to do this without lecturing full-time for the next 2 months. At the moment my head is empty of ideas. I do have a bunch of sheep hearts lying around at school that we can dissect, so that's my fall-back lab for next week. Just need to find some interesting angle on it...

Results - Of Sorts

(Original Post on this Topic)

Good Technique:

This group did a nice job of keeping the detergents within their respective wells. The row of 3 smaller wells with virtually no change were for plain water (control, center well), Woolite (top of picture between 2 & 6), and ALL (lower portion of picture between 3 & 5). There are no enzymes in either of those two detergents.

Bad Technique

This group was either careless with the drops or jostled the petri dish around after drops were in place. The enzyme action is all over the place, and no useful data can be gathered.

However, of the 15 pairs in my class, we had about 12 with good results, and consistently Tide & Cheer worked best on the gelatin. Don't know if that translates into better cleaning action on real stains with real clothing, but I will encourage the student from yesterday to pursue that angle of investigation.

Science is a messy business

A fellow on a biology listserv just blasted cooperative learning and declared, without hesitation, that kids learn best when a teacher stands in front of the room and explains things to them. I hope we one day get past this "one true way to teach" false choice that so many educators are hung up on.

I wonder what his labs are like? I ask, because I have done a series of lab activities lately that were quite messy. Their original purpose was content based - I had a specific content objective that the lab was supposed to demonstrate. In each case, however, I have wound up teaching more about the scientific process than the content, because if I am honest with my students (which I ALWAYS am :>) and help them analyse the results and draw valid conclusions, then all the labs have been inconclusive - they do not conclusively demonstrate the content objective I started with.

Now, I think this is OK, or even pretty cool really. Students learn how difficult it is to control all the many variables that might influence the outcome of an investigation. They learn about the limitations of our measuring tools, about the importance of following a procedure precisely and consistently, the importance of repeated trials or large samples, or carefully recording results and calculating averages, e.g. They even get ideas for exit projects - either re-do one of the experiments and try to clean up some of the mess, or they think of other possible questions to investigate.

A concrete example. I found this series of activities on enzyme action. I am only using the one activity (Mello Jello) to test the effect of different detergents on dissolving the proteins in Jello - some of the detergents have enzymes, some don't:

The jello is prepared and poured into petri dishes, after adjusting the pH with sodium carbonate. Students use a straw to poke wells into the jello, then place a few drops of detergent solution into each of the wells. Tomorrow they will measure the change in the diameter of the wells after extracting the liquified jello with a pipette, presumably the ones with greater enzyme action will dissolve more of the gelatin. I've left out a lot of details, but it's a pretty nice set up, if it works. Of course the set up isn't that easy for 8th grade students. Some of them still have motor skill issues.

I didn't make it any easier for them. I made the gelatin a little too soft, so extracting the plug from the wells was a little difficult. Students had difficulty placing the drops in the wells with the detergent, spilling drops all over the place, probably contaminating some of the wells.

At the end of the period a student asked if she might be able to actually test detergents on clothing as an exit project. She made that connection herself, I didn't suggest it. I think it's a great idea if she pays close attention to the role of enzymes in the process and investigates the variables that affect the enzyme action, the organic molecules that the enzymes work best on, etc. I have seen this activity done poorly, where the only point was to do a product test and little or no science content was developed from it. But investigating enzyme specificity, pH, temperature, etc. seems like a valuable enterprise to me.

I have no idea what results we will get tomorrow. If the results are inconclusive, that's OK. Students will have learned some lessons about the scientific process and they are at least thinking about enzymes, meaning that they might actually be curious enough to pay attention when I have to "explain" it to them.

(Follow up post)

Disappointment

I went through the old regents exams and pulled out as many questions as I could about the digestive system for a test. There weren't that many that dealt exclusively with the digestive system - I could only find 8 questions out of 9 previous exams that I could use. There were a few of other questions that included the digestive system, but they were concerned with how the digestive system interacts with other body systems, so I couldn't use them for this particular test. I supplemented with a couple of questions from their textbook.

I was not pleased with the results. About 2/3 of students failed the test. I'm not sure where I went wrong. I think I asked the right kinds of questions for the research part of their projects, I had students perform presentations for the class on the digestive system, and in the end I went over all the details in a lecture/discussion format just to fill in any holes in their research and answer any lingering questions. I think I covered pretty well the content that was on the exam, without "teaching to the exam" so to speak. I did not teach with the actual exam questions in mind (i.e., give them practice questions that are paraphrased versions of the test questions), but I taught what the students would need to know in order to figure out the questions.

I could and probably will assign part of the blame to the students. They are simply not working as hard as they should be: Often they go through the motions, complete the assignment, but are not always fully engaged in the thinking part of the game. I have to say that on some level it bothers me that an "accelerated" class doesn't take more pride in their work or go beyond the minimum requirements of a task.

So now what do I do given these circumstances? If students aren't working hard enough, it is of course my job to bring them around. I may have to do what I've been loathe to do until now - start calling parents, sending home tests to be signed, all that nonsense that just reinforces the forced learning mentality - learn or else! But maybe that's just the nature of middle school students, even "high" achieving ones.

Digestive System Model: Photo

A rough idea of what the models looked like - balloons and construction paper. One of the students made the labels as an extra part of the model for hanging in the classroom - it's a nice touch and I wish I could incorporate it into the assignment, but with space being limited, and my room totally overused, it just isn't practical to have 16 models of digestive systems hanging around for other kids to come in my room and knock down.

From mouth to anus is about 25 feet, this model being roughly actual size.

Click here for previous post on this topic.

Guinea Pigs

Fridays are bad days to plan things like presentations, labs, new material, etc., and today was true to form. About a third of my class was out for some kind of musical performance and of course they weren't all from the same group, so several groups had missing members. I also left my camera at home, so no photos till Monday.

Actually a good thing it turns out. In spite of the missing persons, I decided to go ahead with a volunteer group for one presentation. I wanted to use them as guinea pigs, and told them as much when they volunteered, and gave them extra credit for going first - it's only fair since they will make a lot of mistakes that others will learn from (hopefully). And mistakes they did make. They were nervous, which reinforced the need to be prepared and have notes - it's hard to talk off the top of your head when your nervous. A few members of the group didn't know their stuff, so it gave me a chance to ask questions to let the others know what they would be expected to know. They also found out that there's a difference between being able to answer a teacher's questions about a topic and being able to explain something without prompts from the teacher. They didn't speak clearly or loudly enough. Some of them had poor body language, staring downward, fidgeting, etc. Some of the students seem to have learned more about teaching from sitcoms than from observing actual teachers: I don't think I've ever heard a real teacher say, "Now class, today we are going to learn about the digestive system..." - you have to imagine the kid putting on his mock friendly teacher face and reciting that line.

The other students rated the whole group' presentation based on the rubric. I rated individual students. In general they were a bit more generous than I was, which is OK. I will give a final score based on an average of the individual scores and the group scores.

The scale models aren't quite living up to my expectations. They all look pretty much the same: Once they saw a group using balloons for some of the parts, everyone wanted balloons. Making it a group project in class was part of the problem. In the future I would probably make it a homework assignment - they might get a little more creative if they have to look around the house for materials or go to the dollar store or grocery store and find something to work with. Class time was probably better spent preparing the presentations, working together on the research.

Final Parts of Digestive System Project

The basic strategy and introductory components of the project are in this post:

Is eating a "waste" of time?

I've elaborated on the details of the nutrient digestion, as well as a rough guide to the sizes of the various parts of the system to be used for the scale models. The whole project write-up can be found here:

A Journey Into the Digestive System & Beyond

and a set of guidelines and rubric for the presentations.

Guidelines & Rubric

The rubric is an adapted version of a generic presentation rubric from:

Teach-nology

Tomorrow are the presentations. I will post a picture or two and report on their performances.

Is Eating a "Waste" of Time?

I did a little project a couple of years ago on student misconceptions and the conceptual change model. I chose to do my lesson plan on digestion, specifically the fate of the food we eat. In my preliminary research, I found that many students have this idea that the food is eaten, goes through the digestive system, and emerges as waste from the anus (giggles all around). When asked about how much of the original food leaves the body, the numbers were extremely high - 50%, 90%, even 100%. This is quite understandable given our personal experience with said waste and no way of explaining the volume of it produced. Students have this abstract idea that food is needed for energy, but for all they know we somehow extract the energy (whatever that is) from food in the digestive system itself and then eliminate the food when we're finished "using it." Few students seemed to have any conception of how the food is used for growth, maintenance, repair of our own tissues/cells or what energy is. There are a lot of lessons suggested by these misconceptions, but at the time I was taking this class I was required to produce a single lesson plan that would address the misconception. I don't think it was very effective.

For my regents classes I wanted to start with the misconception, so the title of this post was my AIM. As a DO NOW I asked students to describe the fate of food from start to finish, expecting the misconception again to come out in their responses. They were however a little too saavy and mostly mentioned the part about breaking down food into smaller particles that were absorbed into the bloodstream and carried to the cells.

From the misconception, I planned a short project for students to do some cooperative group work, researching the structure and function of various parts of the disgestive system, jigsawing with other experts, then re-convening to put it all together into a coherent narrative. As part of the project, students will construct a scale model of the digestive system - schematically conceived - and use the model as a prop when they present. Each person in the group is responsible for detailing the fate of one nutrient - carbohydrate, protein, lipid. Here are the details:

A JOURNEY INTO THE DIGESTIVE SYSTEM & BEYOND

Your Task

1. Describe the fate of one nutrient in the human body:


a. A protein


b. A fat/lipid


c. A carbohydrate – starch


d. A carbohydrate – sugar.


e. A carbohydrate – fiber

2. Describe what happens if something goes wrong in the digestive system

--Describe real conditions that affect humans.

3. Create a scale model of the digestive system using everyday materials such as
cardboard, fabric, paper, etc.

Procedure:

1. Form groups of 4.

2. Each group member will become an expert in one of the following parts:


a. Mouth & Esophagus


b. Stomach


c. Small Intestine


d. Large Intestine & Accessory Organs (Liver, Pancreas)

3. Jigsaw: At different times, experts for each part of the system will get together to share notes. Then you will return to your main group. Since the different parts of the system work together, you will need to understand how all the parts work together. (See details)

4. Create a storyline detailing what happens to your nutrient. (See details)

5. Create a scale model of the digestive system. (See details)

Presentation:

Each group will have a 5-minute presentation. You will use the scale model as a prop to help you tell the story of your nutrient. (See rubric).

I will post some more of the details as we progress. Here are the original questions I've asked students to research:

Part 1: Basic Research (Use extra paper if needed)

• What does digestion mean?
• What is the basic structure and function of your organ/organs.
• What is the organ made of (what kinds of cells, tissues, etc)? What does the organ do?
• What do the specialized parts of the organ do?
• What does the food look like before it is worked on by your organ? After?
• What kinds of nutrients are digested by your organ/organs?
• What is the sequence of events within the whole digestive system? (Numbered list.)
• What happens if some part of your organ/organs malfunction? Explain, name a disorder.
  
  

Creating Models as Inquiry Process

It's been a terrily busy week with class & parent teacher conferences and the like.

OK, so I presented the DNA modeling activity in my curriculum & instruction class Monday night. I'm still not clear in my mind to what extent the activity is an inquiry activity. I got some good suggestions (below) on how to make it more of an inquiry activity, but as it was carried out I remain skeptical.

First, what is inquiry? One of my problems with this term is that it means so many different things to so many people. In order to answer address the question, "Is it inquiry?" you first have to define the term.

I like the inquiry framework on the TIEE website that shows inquiry as a sort of continuum with totally directed instruction at one end and open ended inquiry at the other. I suppose one could argue for this type of modeling activity to fit within their "guided inquiry" definition based on the level of student ownership - in this case, that was basically in the analysis & presentation column. Everything else was pretty much given - the question, the method, & the "data collection," which didn't really apply in this activity. In the future I would take some suggestions from my classmates and allow students more freedom in devising a model of their own. I would have the following conditions, the students would decide how to meet those conditions:

1. Must be a model made up of repeating parts, just like real DNA. In other words, must be made by linking together 2 separate strands, each strand made of distinct phosphate groups, sugars, bases. May be organized into nucleotide groupings, but...

2. Must be able to replicate by "unzipping" and then adding nucleotides.

3. Must have a color code for the base pairs.

4. Must have the basic shape of a segment of DNA - "ladder" - not necessarily helical - for this activity.

I might refine the criteria a little more before I have to teach this again next year.

A final note. The definitions of inquiry on the TIEE site and others often seem to be limited to studies that require the gathering of data to answer a research question. However, making models is clearly a part of what scientists do (even if it's just a preliminary step toward formulating research questions & hypotheses) and the NY State intermediate level standards include making models:

Interconnectedness

Key Idea 2:

Models are simplified representations of objects, structures, or systems used in analysis, explanation, interpretation, or design.

2.1 Select an appropriate model to begin the search for answers or solutions to a question or problem.

2.2 Use models to study processes that cannot be studied directly (e.g., when the real process is too slow, too fast, or too dangerous for direct observation).

2.3 Demonstrate the effectiveness of different models to represent the same thing and
the same model to represent different things.

Again, not to be pedantic, but these standards for modeling are not included in the "inquiry" standards but the "interconnectedness" standards. It seems to me if the word "inquiry" is to have any meaning, then it cannot be so broad as to lose all it's original meaning related to "inquiring" or asking questions. My bottom line feeling, and I'll stop here, is that in the usual educational all-or-nothing approach to teaching strategies, a lot of useful and important science teaching practices were being cast aside because they weren't "inquiry." Now the desire to include those useful strategies has resulted in a broadening of the term inquiry to include those strategies. The way I see it, building models may be part of an inquiry activity if the model is used to generate questions & hypotheses that CAN be investigated, but the model-building itself only fits within a rather loose definition of inquiry.

(It's getting late & I'm talking off the top of my head. Maybe I'll continue this train of thought & put more research into it for my final paper.)

Expenses Update

In a previous post I discussed some of the extra costs of teaching and vowed to keep a running log. I'm having trouble keeping up with some of the nickel & dime stuff, so I'll just have to estimate. By nickel & dime, I mean the occasional candy or (more rarely) soda that I buy for my helpers and sometimes grocery store/$.99 store lab materials like seeds, cups, pasta, etc. I do have a few larger expenses to add to the total:

Previous total: $347.00 (I'm also rounding off from now on)

Pizza partys for both regents classes: $150.00 (including sodas, delivery tip, etc.)

Computer cable for scanner: 10.00

Stenographer pads for use as Exit Project Journals x 60 = $55.00

2 cases Staples multipurpose paper: $38.00 (sale price)
Nickel & dime since September: 100.00

Total: $700.00

Part A Lab Report: DNA Structure

For future reference - click on the picture which links to the related post.

And here's a student lab sheet. This is the one where I asked the students to compare the model to reality. Interestingly, today we viewed a portion of the PBS/NOVA video: Cracking the Code of Life. The scientist in the opening scenes doesn't do such a good job of describing how DNA is different from the 3D model being displayed by the program's host. (Don't ask me for names, it's been a long week!)

UPDATE: The scientist is Eric Lander, Director of the MIT Center for Genome Research, and the correspondent is Robert Krulwich, whom you may remember as an ABC Nightline correspondent. Lander does note that the model looks like DNA in a "cartoon" sort of way, but doesn't elaborate.

!

The kids still have a hard time with the concept of scale. The student here is trying to express an idea we discussed in class, but she doesn't completely understand it yet. Namely, in one sense our model is much bigger than real DNA, in an obvious sense. In another sense, it is much smaller - we have only 5 base pairs in our model, where a single strand of DNA contains 10's of millions of base pairs. If our model had that many base pairs (using pasta & pipe cleaners) it would be over 1000 miles long! We actually did the math on this in class. Some of the students totally misinterpreted this number - "Wow, you mean we have 1000 miles of DNA in one cell" Well, no, if we enlarged a strand of DNA to the size of our model, it would be 1000 miles long...etc. Actually the fact that the DNA in one cell laid end to end would equal about 2 meters is pretty mind boggling in itself. Just multiply that 2 meters by the 50 trillion or so cells in our bodies, and that's a pretty significant distance also! (100 trillion meters = 100,000,000,000 Km = 62,000,000,000 miles roughly).

I probably went overboard with some of the DNA material, but it's hard to gauge how far to take it. The last exam (January 2005) is pretty heavy on the genetics material, I plan on using the questions for their unit test tomorrow. We'll see how they do.

UPDATE

Pasta DNA Models

I can't remember where I got this idea from, but I needed some easy & cheap way for students to be able to create a concrete model of DNA. Pictures in a book just don't do it. So we created these models with pipe cleaners & pasta.

Students used penne for the phosphate group, fiori make the sugar, pipe cleaners of different color make the base pairs. String binds the pieces together. We used the models to visualize the structure, and to simulate replication. Below is a sample of a lab sheet produced by a student. I did not choose the absolute best example - it has some deficiencies, but it's pretty good.

Updated:

I also asked (as I always do) students to consider how the model is accurate and how the model "fails" (I left that part off the lab sheet).
I actually included the question on comparing model to reality in part A, which I will scan later today. This scan shows part B, in which we replicated our pasta DNA. The drawings are simplified, I did not want them spending time drawing pasta shapes where the emphasis was on the process rather than the structure.

(Click on picture for larger view)

I will discuss the concerns I have about teaching molecular genetics in a subsequent post. I have a lot of concerns about how to teach the subject using an inquiry approach, although one could argue that making models fits within an inquiry approach - I'm just not sure that the model making itself suffices...

Update/Note: Flatbed scanners are a great way to get quick easy images of relatively small, relatively flat objects and the lighting is pretty good. The pasta DNA model above is the product of a scan, not a digital camera.

UPDATE - Revised lab sheets

Lost That Rhythm

Just when I was getting into a blogging rhythm, along came the end of the marking period grades, the beginning of the new semester where I am taking a course again, and now getting up early to go in and mark 8th grade science performance exams before school everyday for the next 2 weeks. Not surprisingly, with all the stress, I've caught a cold to slow me down when I need to speed up.

On the positive side, I just bought a laptop last week and I'm already wondering how I ever got along without it:

Dell Inspiron 600M

Pentium M 725 - 1.6 GHz, 14.1" screen

512M Ram

Intel PRO/Wireless 2915 Internal Wireless (802.11a/b/g54Mbps)

2 yrs tech support

etc....

$1,070.68 including tax & shipping

Nice, reasonably lightweight, reasonably fast - at least as fast as my (admittedly old) desktop at home. The internal wireless card is really nice, reception at home is much better than what I am getting from the older USB based stuff on my desktops. I have wireless access at my school and can hook the laptop to a projector and show animations and other useful web resources to the whole class.

I had been fishing around since early December, watching the prices go up & down, thinking a few times that I let the lowest price pass me by, but this price with 2 yrs tech support was the lowest I had seen for a while, so I took the bait. I checked everyday with gotapex - they post coupons and deals that are hard to find or non-existent on the Dell site itself. This particular deal was $500 off a $1499 or more Inspiron. I think the deal is still on.

I also purchased grading software (ThinkWave), after realizing this marking period that I can't possibly give grades based on weighted assignments by plugging numbers into a calculator - just too labor intensive. So I'm essentially tossing out the old paper & pencil binder with lesson plans, grades, attendance, and going high tech from now on. It may take a while to get the efficiency thing down, but what I was doing before just wasn't working for me.

January 2005 Regents

Hello, Annie Chien here. Guest Blogger, fellow science teacher. So my kids took the January 2005 exam - its part of SOF's effort to stick to authentic assessment. Let me explain...

SOF is a Coalition School (http://www.essentialschools.org/) that focuses on small classes, inquiry based learning/teacher as coach, less is more... While the school sees testing as ONE method of assessing for understanding, it believes that its not the ONLY way. So, for the Regents exams, we designed our curriculum so that the kids have enough knowledge to pass it in January so that they can focus on their research projects in June. This is easy since I see the same set of kids for two years in a row for 9th and 10th grade science (this design used to be called "housing").

SOF use to have a waiver for the Regents exams, but the State mandate took that away. The class of 2007 (who were my students and also the first set of students at SOF to take the Living Environments) had a 92% passing rate. This January, my students received a 97% passing rate (out of 100 students). Several thoughts came in mind. I think in bullets. So, here are my thoughts:

• The 97% is based on the curved score. The passing raw score was a 39 out of 85 possible points.
• Can they cheapen science education any futher?
• Yeah, so I read the exam. It was definitely tougher than most of the other exams. But, hey, I think I taught them enough material for them to all pass it without a curve. I think that the kids were mostly frustrated with the length of the exam. But hey, they really just needed to read each question carefully, then take a couple of extra steps to answer the questions.
• Okay, so it IS a curve and I'm sure their sampling methods were fine. So yeah, if you want to be optimistic, its a good passing rate compared with "others".

So what am I really saying here? I'm happy that my kids passed, but I also feel as though everyone got a free ride, even after all that practice we did, "Yeah, we'll scare you with all the Regents requirement hype, and make the curriculum rigorous like heck, but at the end, we'll just assess everyone on a curve, okay?"

Look, I'm proud of the science curriculum we've set at SOF, and okay, so we are so good at what we do that yes, we deserve such a high passing rate. I just wish I worked in a state where the curriculum and assessment made SENSE.

The exam gave me some ideas that can make my curriculum even more rigorous. Reproduction, genetics, biotechnology - hot topics that it focused on in addition to the usual ecology. We have already great project-based units that encompass the topics, and I'm brainstorming on elaborating on them even more.

After some post-exam group reflection, the kids tell me that the Regents Community review really helped. They said that the talking and listening to how problems were done by their peers helped them recall information better. To some extent, they admitted that my ass kicking (making practice homework count as a quiz, pop quizzes, calling parents) helped.

Regents are over, time to do some real fun science!

Pizza Party

I have a runnning competition going between my two regents classes. On quizzes, tests, exams, etc., I average the grades and keep a tally of their scores for the individual assessment, plus an overall score. They have been pretty close thoughout the year with one class slightly ahead of the other. Then came the midterm exam, for which I promised the winner a pizza party. And one class really walloped the other, winning by 12 points. Today they got their pizza party and needless to say, the other class cried foul. Nevermind that I've been on their case lately for not putting in the effort and not having what I consider to be a proper work ethic for an "honors" type, accelerated, grade 8 regents biology class.

As luck would have it, that second place group is also my official class, and there's the whole "familial" dynamic here makes them feel particularly slighted. I don't know yet how I will remedy the situation. I really like my official class, but a significant number of students just want to party - clown around, make jokes, socialize, etc. I can't just reward them for nothing. And the thing is their behavior/attitude problems are an issue in homeroom period as well, and their conduct sheet is far from perfect. I would love to be able to just reward the students who do work hard and succeed, but there is no clear divide between the two groups - if you lined the class up and put the worst offenders on one side and the hardest working best behaved student on the other side, everyone else would fall along a continuum between the extremes, with no clear demarcation point between those who deserve to be rewarded and those who don't. Then of course there's the slacker who does well on the exams, and the hard worker who doesn't quite get it yet and fails the exams. It's just an impossible split.

I will discuss the issue with them tomorrow and see if we can come up with a plan. They will need to do something to earn the pizza - I don't mind spending the money once in a while or using class time if they work hard enough to deserve it. If the exam scores had been closer and their lack of effort weren't so obvious, I would have given both classes a party today.

Guest Blogger

Annie Chien is a high school science teacher of regents living environment at School of the Future in lower Manhattan. I have known Annie for a couple of years now, beginning with a class we found ourselves in at CCNY (Evolution). I had not seen Annie since that class, but after I subscribed to the NSTA Biology Listserv (NSTA members only - login required), her name started appearing in my e-mail box as she commented on various questions people had posed on the listserv. Annie stumbled upon my blog and and we have begun talking about regents living environment and some of the issues it poses in terms of, e.g., constructivism and inquiry. She has been teaching the course for six years now, and I welcome her input. I have asked Annie to be a guest blogger here, which she has graciously accepted. I will let her spell out any other professional/personal information she would like to share. Look for her post early this coming week.

Welcome Annie!

Humane Treatment Revisited

(Original Post on Humane Treatment)

After e-mail discussions with Tony Galitsis, retired teacher, science ed specialist, founding member and still active partipant of the New York City Science Coordinator's Network (hope I got all that right), I googled "ASPCA humane treatment schools" and lo & behold, up came Article 17 of New York State Law on humane treatment of animals.

The ASPCA version of New York State Law Article 17 has a little more information, but not much, and indicates it is current as of 2000, amended in 1994. It also includes some common sense guidelines for treatment of animals kept in classrooms as pets or for simple observational studies. They have a printer friendly version as well.

Tony is less optimistic than I am that elementary & middle school students, or teachers for that matter, can carry out animal experiments properly. As I was formulating an argument in favor of such experiments, I found myself thinking maybe he has a point. I still think an outright ban would be going too far (which Tony wasn't suggesting either), whether by school or district administrators, but perhaps some kind of formal review process would be appropriate. This would increase the liklihood that only serious and meaningful studies would be carried out, decrease the chances of inhumane practices taking place.

At this point, however, any such process would probably have to come from the school or district (region in NYC) level.

Elsewhere on ASPCA Website:

Animals in the Classroom: A short article on things to consider and basic guidelines.

Midterm (Regents) Exam Results

Regents Living Environment Exam June, 2004 Version

Average Scaled Score*: 50



High Score: 70



Low Score: 24



Number of passing scores: 1



Mode: 48



Median: 53



Number of test takers: 53 (out of 60 - make-ups not yet given)

*Scaled score is the score that counts in the sense that it is the raw score (out of 85 possible points) converted to the 0-100 scale we are all familiar with, 65 representing a passing grade in most places.

Not the results I had hoped for, but not unexpected for January, half-way through the curriculum. An average of 50 is at the low end of my range of expected outcomes. A lot of questions on this particular exam revolved around genetics and Human Body System/Homeostasis, which are coming up in the curriculum. It was definitely more difficult than the practice version we looked at in class earlier (June 1999).

Still, I expected a few more to pass the exam outright - a couple came close with 63 and 64. A lot of students in the 50's range - actually a distinct clustering at the 48-56 range (29 students), and that represents a range of only 7 raw score points out of 85. I certainly have hope now that everyone who puts his/her mind to can pass this exam in June. A lot of students continue to be confused by the wording of questions and the (non-science) vocabulary can throw them off at times. By June, they will have most of the major content areas covered and they will have seen the exam a couple more times, which means they should be more comfortable with it.

The low score of 10 is really bothersome. 10 points could easily be had by simply marking all the multiple choice questions with a B or C. This student clearly put no effort into the exam, leaving all the short answer items blank. Looks like time to call mom.

Student Blogs

I have finally started a list of student blogs on this page.

I have assigned the blogs for extra credit, with a bonus this marking period for starting the blog and making the first post. So far I have 4 blogs listed. Others have set up their blogs but not posted. Still others are awaiting computer time to set up their blogs.

Here's how the credit works after the initial set up. I will award 1 point for each entry either on your own blog or commenting on another person's blog. The points are added to students' homework scores until they get to 100. After that I start adding onto class participation grade, then quizzes, and so on. The idea is to get students talking to each other about science outside of class. Of course I have to lay down the guidelines and discuss etiquette. Most of the guidelines have already been formulated, it's just a matter of making sure again that everyone understands. You can find the rules here that I posted last year when I was just piloting the idea. You can also find the parental consent forms I am using here.
Of course the current concept is a lot different. I had originally wanted to have a single blog for the entire class, but I abandonded that idea because it depended too heavily on me providing activities and links to the students.

I thought they might be a little more motivated if they had their own personal blogs. I even allow them to write about other topics, but they only get science credit for science posts - everything else is for their own personal enjoyment. I may assign specific questions that I want students to address at various points throughout the rest of the year.

Humane Treatment of Animals

UPDATE: See this post for more info.

New York State Consolidated Laws: Education: Article 17: S 809.Instruction in the humane treatment of animals (Scanned by me - not found on internet)

At the recent professional development session at the Bronx Zoo, a number of teachers asserted that students were not allowed to perform any experiments that involved animals. This was based on information passed down from science coordinators or science supervisors in the school or district.

Just to clear the air a little bit. It may well be that an overzealous administrator mis- or over-interpreted the law, but the law of New York State does not forbid animal experiments provided animals are treated humanely and not seriously harmed. I have never heard of nor seen any New York City or Department of Education regulations that are any more strict than NY State. Here's a quote from the pertinent paragraph (formatting altered for readability):

5. Treatment of live vertebrate animals.

a. Except as provided for in this subdivision, no school district, school principal, administrator, or teacher shall require or permit the performance of a lesson or experimental study on a live vertebrate animal in any such school or during any activity conducted under the auspices of such school whether or not the activity takes place on the premises of such school where such lesson or experimental study employs:

(i) micro-organisms which cause disease in humans or animals,
(ii) ionizing radiation,
(iii) known cancer producing agents,
(iv) chemicals at toxic levels,
(v) drugs producing pain or deformity,
(vi) severe extremes of temperature,
(vii) electric or other shock,
(viii) excessive noise,
(ix) noxious fumes,
(x) exercise to exhaustion,
(xi) overcrowding,
(xii) paralysis by muscle relaxants or other means,
(xiii) deprivation or excess of food, water or other essential nutrients,
(xiv) surgery or other invasive procedures,
(xv) other extreme stimuli, or
(xvi) termination of life.

Pretty common sense regulations. Don't abuse the animals. Do the research ahead of time to find out what ranges of conditions the animal can tolerate without adverse effects. Conduct your studies within that range. When in doubt, and no information can be found, reconsider the experiment.

The only references I can find to NY City guidelines can be found in the New York City Board of Education Science Safety Manual. No prohibitions against animal studies are to be found in this document. I sincerely invite anyone to find contradictory information in writing from the state, city, or department of education.

Exit Projects & Midterms

I'm now seriously considering having students turn their genetic disorder reports into an "exit project." They are already doing quite a bit of research and we have spent a lot of class time on the projects. It would only be a small stretch to now focus on finding data that would justify calling their work a "Secondary Research" project that qualifies as an exit project. It's not my idea of a perfect project - the data part will be quite limited - but it's at least as good as some of the examples given in the NYC Exit Project Booklet (Warning - badly scanned by DOE).

I was developing the rubric for their projects this morning and realized how close they were to having a project that satisfies the formal exit project requirement. That would take care of one of the many burdens my regents students face - and they would be finished without even realizing they had finished it! We could then focus more of our energy on the "important" stuff like completing our labs and passing the exam. You can download my rubric here. It's a modified version of our old district 6 project rubrics.

On another note, I've decided to administer an old Regents exam as their midterm - the entire thing. This will give them a sense of the scope of the exam and the language they have to get used to - they always complain that I use such big words when I talk, wait till they start reading the regents exam! I plan to give them two scores.

First, I will let them know what their score would be if this were the real thing and they had to take the exam today - considering we are only half way through the school year, a real score of 65 would be nice (that's a raw score of 41 out of 85 possible points on the January 02 exam). In reality, many of the ecology concepts on the exam were taught in grade 7 plus many of the questions can be answered just by paying close attention to the questions and thinking, so I'm hoping that most students will be close to the 65 score.

I will then take their real scores and distribute them on a curve for a score that will go in my record book and be recorded on their report cards as the midterm exam grade. I expect that real score of between 50 - 65 to be the average for my two classes. Then again maybe I'm in for a serious letdown. Either way, the results will affect my decisions about what to do with the remainder of the school year. I've been worried for some time that we are not making enough progress. I hope this practice exam puts my mind to rest. If not, I may have to change tactics and get much more structured in my approach.

Haloscan commenting and trackback have been added to this blog.

Urban Advantage

I was asked last week to help “facilitate” some of the professional development sessions for Urban Advantage (UA). This is a collaboration between the New York City Department of Education and the New York City Science institutions – The Bronx Zoo, American Museum of Natural History, Hall of Science, Botanical Gardens, etc. You might think such an effort involving over a million dollars in funding from the city council might have some online information, but at the moment such information is lacking so I can’t link to any sites.

I am working for three Saturdays with the Bronx Zoo sessions. A team of about 10 or so science teachers from different school regions is hosted by the zoo, instructed by a zoo scientist, Jennell Ives. She is very knowledgeable and competent, which is as one might assume for an undertaking such as this. As science facilitator in district 6 a couple of years ago, I was always impressed with the scientists we worked with at the Museum of Natural History who offered their expertise to help teachers. This is my first exposure to a scientist working at the zoo and I can only hope that all the other institutions have such a great instructor.

The main focus of the initiative is helping teachers utilize the science institutions to help students in grade 8 complete their “exit projects.” My regents students are also expected to complete an exit project in addition to all the other demands, which have been alluded to in earlier posts. The term “exit project” is an unfortunate one, because it is really part of a larger requirement that students complete a long-term scientific investigation every year, pretty much from kindergarten through high school. The “exit” part was added a few years ago really as an escape hatch for students with failing grades in science who might nonetheless be allowed to “exit” anyway with an acceptable project completed. It’s a bit convoluted, since no one is ever kept back based solely on science grades anyway, so why the need for an escape mechanism is entirely unclear to me. Perhaps because of this, the real intent of the projects was never really articulated to anyone’s satisfaction and repeated requests by science coordinators to get the Board of Ed to clarify what exactly it wanted from these “exit projects” were never answered.

Nonetheless, we are all pretty much unanimous in our agreement that long term investigations – such as controlled experiments, field studies, secondary research, and design projects – are a worthwhile and important part of science education. So we promoted and pushed the concept at the district for a long time. Back in the day (before the Bloomberg/Klein regime) our district (6, in collaboration with 5 & 3) pretty much dropped the “exit project” name and instituted project requirements for grades 5-8, incorporated into our curriculum frameworks along with content objectives derived from the NY State Core Curriculum.. Unfortunately, now that this city-wide endeavor has begun with much fanfare, the term exit project was picked up again and we seem to be stuck with it unless the UA initiative is expanded next year, when the parties involved will have to grapple with what to call the projects once they start getting 5th, 6th, and 7th graders involved.

I was impressed with the the participants, the instructor as noted above, and of course the zoo is a great place to visit. I managed to snap a nice picture of the Inca tern, Larosterna inca, in a very large open air (outdoor) aviary.

DNA Extraction

I had planned to extract DNA from wheat germ. I went through the hassle of finding raw wheat germ (as opposed to toasted, which just about every grocery store has). Two local health food stores didn't carry the raw stuff, the local grocery stores don't carry it. I wound up at the Whole Foods store in the new Time Warner building at Columbus Circle. The wheat germ was actually rather inexpensive at about $1.69 for a 12oz(?) box. I gathered all the other essential elements of the lab. Then someone posted a fairly simple protocol for extracting DNA from cheek cells on a listserv that I subscribe to, so I decided to give that one a try (picture below).

The only real purpose I can see to these labs is to de-mystify DNA a little and generate a little excitement at the same time about it. There's something neat about being able to "see" this stuff and know that it came from your cells and it's just this substance found naturally in all living things. It's not magic powder, it's this goopy, clumpy, stringy white stuff in our cells. My hope is that they will be really intrigued and want to know more about how this funky-looking material determines our traits.

I gave students a choice of following the wheat germ protocol or the cheek cell. It was kind of nice to have the two being followed at the same time for comparison, but it certainly complicated the distribution of materials and discussion of the two protocols.

What administrators don't understand about teaching science

I teach in a school that is probably not unlike many others. We have no real science labs, science is taught in whatever rooms are available for the programmer to put us in. We are a large school: In my grade (8) there are about 5 teachers with about 4 classes each (on average - in reality we teach a split schedule between grade 8 plus at least one other grade, but that's another story. The point is there are about 5 grade-8 teachers and about 20 grade-8 classes!). There are a small number of classrooms (about 3) for each grade that were originally designed as science rooms, but the science part (running water, gas lines, lab stations, etc) were dismantled many years ago. Nonetheless, because they are near the science supply rooms and relatively large, they are at least more desirable than other classrooms in the building. Unfortunately most of those rooms are in fact not used for science but rather as regular classrooms for English, Math, or Social Studies classes. One of the supply rooms was turned into an administrative office. I am lucky enough to teach in one of the "science" rooms.

I'm also lucky enough to be teaching regents biology which provides some guidelines, specific content objectives, and some required labs. It is still not what I consider a "curriculum" and demands a tremendous amount of planning from teachers. The labs, being at a higher level than many of the middle school labs, also require a lot of prep time and a lot of materials, some rather specialized. The DNA lab needs water within a somewhat narrow temperature range (50 - 60 Celsius), test tubes with covers, long stirring sticks, alcohol, and a few other items. All need to be prepared in such a way that 30 students (yes, 30 students) can use them at 5 different tables with a minimum about of spillage or breakage. On top of that, materials usually have to be distributed AFTER students arrive, because the room is used throughout the day by other classes and cannot be arranged at the tables before students enter. Likewise, materials have to be collected at the end of the period because the classroom will again be used by another teacher (for social studies or English) with another class. Now think about making sure all the tables are cleaned after doing cheek cell labs and other biology related activities! For my 7th grade class I have to travel to three other rooms on a different floor. This is pretty typical this year for most of my colleagues, in fact my program is great compared to others. Not exactly my idea of an ideal working environment for science teachers. As you might suppose, we have an incredibly high turnover rate for teachers in general, and - it seems to me at least - science teachers are particularly difficult to find and keep.

Back to the DNA Extraction Labs

If you are thinking of doing one of these labs, don't sweat the details. I used saltwater for the mouth rinse, which may have been unnecessary: I misread the protocol and I remembered using saltwater in a class when I did the cheek cell extraction, so I guess I didn't read that part too carefully. I must say it gave me some perverse pleasure to see the students suppressing their gag responses to the saltwater! I also tried following the correct protocol using tap water as the mouthwash and adding saltwater later. Both methods yielded neat samples of DNA. I was pretty imprecise with the liquid detergent, and didn't have any problems. Wheat germ does indeed give oodles of DNA.

The biggest problem my students had was following the protocol alone and not waiting for me to tell them what to do, or insisting I tell them at every step if it was OK now to do the step. I will take some blame for that. It isn't that often that I give them written assignments or open-ended activities and let them struggle through it on their own. (Note to self...)

The other problem was pouring the alcohol into the test tube gently without letting it mix into the saliva or the wheat germ mixture. The cups I gave them for pouring didn't work so well, probably because of the low surface tension(?) of the alcohol which leads it to spill easily, even from beakers - in trying to avoid spills they poured too fast and mixed everything up. It was a bit of a messy lab, but I think a lot of fun for the kids, and I hope a nice starting point for getting into the details of DNA in the coming couple of weeks.

Lab Lists

Lab list for the next few weeks. Details will be posted as we go along. This is just an overview to keep me focused. Some labs are available online and I have provided links. Others I will devise myself.

These next few weeks are a little tricky. I have to prepare my students for the grade 8 exam, plus get them ready for midterm exams, plus keep moving forward with the content and the labs for regents. At this point we have almost 600 minutes of lab time, which is not where I would like to be. I will need to step up the pace a little in the third marking period so there will be plenty of time for tying things together and test prep in May/June.

1. Microscopy – Introduction/Review, looking at plant & animal cells and various human cells, estimating size with grids. This has to be made from scratch, and depends on what materials I can get my hands on at school or by ordering.
2. Extracting DNA – A “throwaway” lab, more of an attention getter than anything else. I may work some scientific method into it – manipulating a variable and measuring the amount of DNA that can be extracted.
3. Dichotomous Keys – A review for the middle school exam (end of January), also a skill included in the Living Environment curriculum. I’ll probably use past activities for this one.
4. Making Connections – required lab - NY State
5. Digestive System Model – a “design” project. Students will use readily available materials to build a model of the digestive system.
6. Return to mealworms for students who are interested in doing an exit project with them – I won’t force this one on anyone.
   

Completed Labs

1. Yo! Where’s my Peanut – a dinky "close-looking," observation activity.
2. Black Box/Mental Models Lab – mystery in a box, develop mental model using observations.
3. Finches' beaks – NY State Required Lab
4. Mendel’s Peas Simulation - this one didn't go so well, mainly because I messed up the ratios myself!
5. Alien Heredity
6. Mitosis with Pipe Cleaners
7. Osmosis Through an Egg Membrane
   

Genetic Disorder Research Projects

"Disorder" for lack of a better term. It's a little difficult to know exactly what to call the various genetic "abnormalities" (itself a loaded term), which range from obvious diseases like Cystic Fibrosis to the chromosomal disorders such as Down Syndrome to multi-factorial disorders such as diabetes & cancer that sometimes depend to a certain extent on enviromental interactions.

I assigned students to do a long-term investigation of one disorder. I have tried to limit them to the "simpler" disorders involving single genes or chromosomal abnormalities.

Timing is a challenge with long-term studies. If you assign the project too early, the students may not be able to make any sense of what they read. Assign it too late, and the chance to integrate their questions into the curriculum vanish. Since I had broken up my curriculum into non-linear chunks, I assigned the topic a month ago when we were discussing reproduction & Mendelian heredity. I hope to have the projects finished in the coming weeks as we study DNA, genetics & human reproduction.

I'm posting below the list of questions I provided students to help guide their research. They are supposed to come back from the holiday break with most of these questions answered.

Genetic Disease Study for Regents Biology Classes

Answer the following questions in your own words. Answer each question in a short paragraph if possible. You may want to write the question on one side of an index card, with the answer on the opposite side.

• What is the name of your genetic disorder?
• What are the causes of the genetic disorder?
• What is the effect of the genetic disorder on the body – at the cellular level and at the “organismic” level (how does it affect the whole body, what are the symptoms)?
• How does a “healthy” gene differ from a gene that causes the disorder?
• Have scientists identified the gene or genes that cause the problem? Where are the genes located? (Which chromosome? Include karyotype in your report to show location.)
• How common is the disorder in the general population?
• Does the disorder affect some population groups more than others?
• Is the disorder more common in some parts of the world than others?
  Is the disorder inherited? If so, is it dominant or recesive? Or is it more complicated than that?
• If your disease is a chromosomal abnormality, like Down Syndrome, how does that chromosomal abnormality occur? Use pictures to show how it happens.
• What kind of life does a person with the disorder lead?
• Are there any treatments for the disorder?
• Is there any other interesting information you found that you would like to add?

Remember, eventually your paper will need to discuss the relationship between DNA, genes, & proteins. So save any information you find about that, even if it doesn’t make sense right now.

I will create a simple rubric and post later.

The Cost of Teaching

My wife walks into my "office" and says I look like Scrooge poring over receipts on Christmas Eve. That's pretty ironic since I'm actually compiling a list of materials I've purchased this year for teaching - my hard earned money used to subsidize the NYC school system. If you added up the money teachers donate to their classrooms and the money parents donate for their children's classrooms (I have 2 children in public school and there are constant requests for materials/supplies/money in one form or another) the amount would probably equal what many other medium-sized districts in the US spend outright on education:

Let's see, approximately 100,000 teachers, and I'm guessing low at an average of $250 per teacher = $25,000,000 additional dollars donated by employees of the system.

Then let's add in the parent donations - including "candy sales" and other donations disguised as purchases (there's a ridiculous mark-up on fund-raising sales). There are approximately 1,000,000 school children in NYC. Based on my expenditures, knowing what goes on where I teach, and knowing what happens in other schools around the city, I would suggest an average of "only" about $50 per child, city-wide. That's another $50,000,000 in donations from parents to the system.

Grand Total: $75,000,000

I'm way too busy to seriously research these numbers, but I certainly invite anyone else to refute my calculations with real data.

As for my personal expenditures, so far I'm up to $542.57, just based on receipts that I can find quickly. You can subtract $200.00 for "teachers' choice" that we are reimbursed. So out of my pocket would be $342.57 and there is a lot more left of this school year. It doesn't include some purchases for which I haven't found receipts yet. It also doesn't include a lot of nickel-&-dime purchases that I make in cash periodically. Most of the items included are basic supplies that schools should provide for teachers as a matter of course - papers, photocopies, pencils, pens, markers, bulletin board supplies, glue sticks, etc. Some items are for science labs - either equipment that isn't available in the school or consumable materials. I will keep this list updated throughout the year and see where things stand in June.

Science Writing

I have to admit I'm not much of a reader. I subscribe to a couple of magazines, I read selected articles in the newspapers - mostly online versions and way more sports than I should - but rarely do I pick up a book and read it cover to cover, and even more rarely a work of fiction.

I have lots of excuses. I have twin boys (6 years old) so I don't have many care-free weekend days to lounge around reading. I spend way too much time planning for school, which is probably true of most teachers, especially science teachers, so when I do read it's usually researching some topic I'm teaching at the moment. I walk to work, so there's no morning/afternoon subway commute where I could get in an extended reading period. But mostly I just have trouble sustaining the effort needed to plough through a real book.

When I read, it's almost always short non-fiction pieces. And if I can combine reading for pleasure and work at the same time, all the better. I'm sure a lot of people become English teachers so they can be paid to read literature: For me that would just be torture! (How I ever got a Masters in German Literature I'll never know. If reading fiction in English is drudgery, imagine the pain of 2+ years reading fiction in another language - but I digress).

So recently I stumbled on a title that seemed to be made for me. "The Best American Science Writing: 2004." (See excerpts at Amazon.com) A collection of science articles written for various publications including the New Yorker, Vanity Fair, Wired, Harper, NY Times, Discover, and on & on. These kinds of articles are where you can get interesting tidbits to throw into your lessons that make science discussions lively & interesting. Listen to this opening to the lead article in the book:

The television in the dead man's room stays on all night. Right now the program is Shipmates, a reality-dating drama that's barely audible over the hiss of the ventilator. It's 4 AM, and I've been here for six hours, sitting in the corner while three nurses fuss intermittently over a set of intravenous drips. They're worried about the dead man's health.

Great story, interesting tidbit about what happens to the individual cells of the body after brain death:

In the moments after death, a cascade of changes sweeps over the body. Potassium diminishes and salt accumulates, drawing fluid into cells. Sugar builds up in the blood. With the pituitary system offline, the heart fills with lactic acid like the muscles of an exhausted runner. Free radicals circulate unchecked and disrupt other cells, in effect causing the body to rust. The process quickly becomes irreversible. As cell membranes become porous, a "death gene" is activated and damaged cells begin to self-destruct. All this happens in minutes.

I'm enjoying the stories so far, and looking for the time to read more of them!

Curriculum Revision 1.2

After struggling through cell processes and promising students that diffusion, osmosis, and active transport would be really interesting and important when we get to study the human body, I realized I could not put off that unit till the end of the year.

It just makes no sense to me to teach these cell biology topics out of context. I still believe in teaching abstract fundamental concepts on a need to know basis. Why do textbooks insist on presenting a whole separate unit on cell processes? I will cover enzymes when we get into digestion, where enzymes play an obvious and key role. DNA replication and synthesis will go with reproduction. Of course diffusion, osmosis, and cell transport are part of just about any human body function we might want to discuss.

This puts me again in the difficult situation of having to "cut & paste" from various chapters in the book, but I just cannot fathom right now trying to teach enzymes the way it is presented in the books.

On another level, it probably makes more sense to cover human body in winter, since our "subject" is right there in the classroom. No need to go on a field trip to see one or think about how things work. Other concepts that I had planned for this winter are probably better covered in spring when we can get out of the classroom - ecology in the parks, evolution at the Museum of Natural History (I'm hoping that my principal will allow field trips again by then!).

New York Hall of Science & Field Trips

In my 3 years as a staff developer at the district office, we were constantly looking for ways to encourage greater use of science institutions at our disposal in New York City. We've got the Museum of Natural History, which is a great resource for those who can get there easily - a single visit just doesn't cut it. It's my favorite since I'm partial to biology & geology anyway, and it's easy for me to get to. We've also got the NY Hall of Science (more below), parks and environmental study centers, zoos and botanical gardens - all within relatively easy reach.

I personally love field trips with my students. I find that most students are quite well behaved, that they are greatly benefited by getting out of the neighborhood and it allows students and teachers to interact in a much more relaxed atmosphere. It often improves relations with students back in the classroom. They always remember the field trips, and if done properly they even engage in formal learning activities without the usual complaints - in fact, they will enjoy the trip more if there's some structured activity like a worksheet or other written assignment where they have to focus on some aspect of the experience.

On Friday I took my class (along with 3 other teachers and 2 other classes) to the NY Hall of Science in Queens. For us in Upper Manhattan, this is a bit too far to travel, at least by public transportation. It was about 1.5 hours in both directions and we didn't leave the school until 9:00. That left us about 2 hours in the Hall, including check-in and lunch. It's a great setting for students. A relatively small space, very open, tons of hands-on activities that are well made - plenty of "wow! that's cool" exhibits to keep the kids enthusiastic. The other great thing about the Hall is that they have lots of "explainers" lurking around to interact with the students. Students kept themselves engaged and were pretty free to roam the exhibits in plain sight of teachers or other adults. This is quite a contrast to the Museum of Natural History, which is a very large, stuffy, don't-touch-anything kind of place where security is constantly scolding someone for not being supervised or touching something or leaning against something, etc. Not really a good place for large groups.

In spite of the distance, I would still take my other classes to the hall if I could. My school, unfortunately, sees field trips as little more than a waste of instructional time annoyance. Requests for field trips are met with skepticism, and I almost always leave the principal's office after my request feeling guilty and apologizing profusely for making the request. In this instance, the principal reluctantly allowed the trip but was emphatic that there would be no more field trips until after the standardized tests. I could go off now on NCLB, but frankly there's always been an anti-field trip bias at the school. It just shouldn't be that way. I know other schools actively encourage field trips and recognize their value. There should be a distinction made between an academic activity and a trip to the theater to see The SpongeBob Squarepants Movie, for example.

As for my regents biology connection, I had hoped to spend some time on the Marvelous Molecules - a gigantic sugar molecule model and other biochemical concepts. But our schedule in the museum was cut short by the long travel time.

Absolute Beginner

It's moments like these when I feel totally incompetent. I've been teaching 13 years now, and yet here I am, fumbling around trying to find my way through a science curriculum like any other first year teacher. I'm spending too much time on certain topics but still finding too many of my students aren't keeping up. I'm rushing topics that should be prior knowledge but about which my students are understandably clueless - basic chemistry concepts, e.g.

As I mentioned in an earlier post I've been struggling with sequencing and pace pretty much from the beginning. This being an "accelerated" class for 8th graders in some ways complicates things, since I know that my students don't have the background knowledge that would be expected in a 9th grader, but from what I've heard from other high school teachers, large numbers of 9th graders aren't exactly prepared either. So I would likely be running into many of the same issues in another setting.

This past week I tried to cover 6 weeks of grade 8 chemistry in one week. A lot of lectures, discussions, visualizations, but not much in the way of activities. I figure we will continue using the vocabulary in studying cell processes over the next few weeks and indeed throughout the rest of the course, so a crash course was in order. I hope that with repeated exposure to the concepts in the context of cell biology, ecology, and human biology it will begin to make sense at some point.

As an example, we just set up an experiment looking at osmosis in chicken eggs. It's an old activity involving vinegar to dissolve the shell, then soaking in distilled water or corn syrup and observing changes in the mass of the egg as water diffuses into or out of the shell respectively (here's a good write up of the experiment in PDF from Power to Learn - there are lots of versions online so I won't attempt to recreate another one here). This is a rich activity. We discussed what an egg is (review from previous lessons where we talked about sperm & egg - sexual reproduction), special features of the chicken egg, organic compounds found in eggs (proteins, lipids, carbs, nucleic acids). Next we will consider the chemical reactions that dissolved the shell in vinegar and the diffusion of water molecules across the semi-permeable membrane. Along the way we will have to review or learn from scratch simple solution chemistry - solute, solvent, concentration, etc. On top of all that, we will perform the activity as a controlled experiment and discuss variables, controls, construct tables & graphs, analyze data.

A former colleague who is now a principal argues that living environment teachers should try to teach a few topics and teach them well. If students pass the exam with a 65 then that's sufficient. (Addendum: The curriculum is simply too broad to hope that you can meaningfully cover every topic that might appear on the test). I'm OK with the idea of teaching fewer formal topics and teaching them well - in fact, if the units are as rich as the egg unit, then the students may come out understanding significantly more, but the 65 doesn't sit with me. Especially with my 8th graders, where I'm afraid if they don't do better than that the schools may find a way to reject their middle school regents course and require them to take it all over again in high school. I hope I am teaching at least as well as they can expect to be taught in a high school - otherwise what's the point?

I really like teaching this curriculum. I'm enjoying the noticeable maturation of my grade 8 students, all the more obvious since I'm teaching a 7th grade class at the same time and can really see the difference! I don't think I can ever go back to 6th grade and 7th grade is barely tolerable. It remains to be seen whether I move up another grade next year or find a school that can give me a full grade 8 regents program. I almost definitely will not be at my current school. See next post for one example of why.