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