Monday, December 24, 2012

On trick questions

Sometimes prattling on about things I'm passionate about, like balloons in a bottle, is like chatting about my fantastic rubber band collection.  
You have been warned.

The new AP Biology exam requires thinking
, requires it, and not much else. The sample questions are thoughtful, dense with information, and ask for reasonable conclusions.

It no longer is (if it ever was) a cram and dump course.

And never before have I been swamped with so many accusations that my tests have "trick questions" for questions that are just basic questions of understanding.

There's a chasm of difference between "heat" and "temperature," and  if you know the difference, it's very easy to get that while a cup of hot tea has a higher temperature than the ocean, the ocean has vastly more heat.

You can slog your way through definitions or equations to get there, but once you own the concepts of heat and temperature, the distinction is as obvious as a bow tie on a banana. Any question about comparing heat in a cup of tea and the ocean becomes embarassingly simple.

Or embarrassingly tricky.
Here's one from the practice exam:

Simple cuboidal epithelial cells line the ducts of certain human exocrine glands. Various materials are transported into or out of the cells by diffusion. (The formula for the surface area of a cube is 6 × S2, and the formula for the volume of a cube is S3, where S = the length of a side of the cube.) Which of the following cube-shaped cells would be most efficient in removing waste by diffusion?

There are several ways to get this, perhaps the easiest just realizing it takes 8 of the choice A boxes to make the volume of 1 choice B box, obvious to some on first blush.

How does something like that even become tricky?
What happens along the way that bright kids doubt their own ability to think?


Quilbilly said...

I am glad that they have revamped the AP Bio test. I taught it for a number of years and I was never more relieved than when my next door teacher agreed to take it over. It reminded me of a comment a friend of mine made in college. He told me how much he loved biology until he became a biology major. I single handledly probably ruined biology for about 100 students. Luckily we are a small school or it would been more.
I am not sure how my neighboring teacher does it but she does a lot better job with it than I ever did. The kids like it and do well on the test.

Lee said...

The other day while I was going through some boxes I came across my rubber band ball (not huge, but respectable). Some of the outer bands are starting to dry out, and I almost tossed it. Have I found someone to adopt it perhaps???

doyle said...

Dear Quilbilly,

I really disliked AP until this year--I did not volunteer for the class,and tried hard to get out. Happy now, though!

Dear Lee,

Um, no thanks. =)

Malcolm said...

that's an AP question? we teach that concept in gr8 sci and continue it on through grade 12 bio!

doyle said...

Dear Malcolm,

It's a sample question, not a "real" one, directly from the new manual (open online to all of us).

But I'm fine with it being a basic concept--I think that's the point. There are about 145 learning objectives, and not all of them are as simple, but not everything has to be sophisticated to be worth knowing.

Take a look at the rest o the sample questions--I think it's a much better course now for several reasons, and I think the exam will create real separation between those who just memorize and those who understand.

Sue VanHattum said...

Where is the sample test?(Is the pdf found here what you have in mind?

I don't know how diffusion works in order to transport something, so I wouldn't know which answer made sense.Can you tell a bit more of this story?

Jeffrey Michals-Brown said...

Yeah--what Sue said. What is "efficiency" in this context? At first glance, it's just the ol' surface area:volume bit (smallest cell wins because it has a greater area:volume ratio), but on reading the question more closely, I'm not so sure!

Mariel said...

Hi, I'm currently a sophomore whose taking AP Bio, I'm a bit worried about this test since this is a "guinea pig year", is there anything that i need to focus on in order to get a good score? Thanks so much!