Friday, March 04, 2005

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.

Thursday, March 03, 2005

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.

Monday, February 21, 2005

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.

Tuesday, February 15, 2005

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.)

Saturday, February 12, 2005

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

Thursday, February 10, 2005

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

Wednesday, February 09, 2005

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

Tuesday, February 08, 2005

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.

Wednesday, February 02, 2005

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!


Tuesday, February 01, 2005

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.

Sunday, January 30, 2005

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!



Friday, January 28, 2005

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.


Saturday, January 22, 2005

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.


Thursday, January 20, 2005

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.


Tuesday, January 18, 2005

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.

Monday, January 17, 2005

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.

Saturday, January 15, 2005

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.

Tuesday, January 11, 2005

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.


Thursday, January 06, 2005

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