Kevin Drum reports receiving an email from a professor of physics denouncing the Advanced Placement test in Physics:
It is the very apotheosis of “a mile wide and an inch deep.” They cover everything in the mighty Giancoli tome that sits unread on my bookshelf, all 1500 pages of it. They have seen not only Newtonian mechanics but also optics, sound, electromagnetic theory, Maxwell’s equations, special relativity, quantum mechanics and even AC circuits. They don’t understand any of it, but they’ve seen it all. They come into my class thinking, by and large, that objects move due to the force of their motion and cease moving when that force has all been used up; that tables do not prevent things from falling by exerting a force but by simply being in the way, blocking the natural motion; that when a tossed coin reaches the top of its flight, the force of gravity and the force of its motion are balanced; that opposite charges are attracted magnetically; and I could rant on for a while.
Anyway, this makes me curious. I have lots of readers who teach at the high school and college level and I’m wondering what they think about this. Are AP tests (and AP classes) all they’re cracked up to be? Or are there lots of you who grit your teeth but secretly agree with my correspondent? And is this just a physics thing, or do history and lit teachers have the same complaint?
The comments are remarkably civil for Calpundit Monthly, but I’m going to respond here anyway (after the cut).
First of all, there are two different versions of the Physics AP test. One of them (I believe it’s “Physics B,” but I’m too lazy to check) is the sort of giant survey course that Professor Camp complains about, using an algebra-based book with all the problems that entails. (I’ve used the textbook he mentions, and I wasn’t terribly impressed.) The other version of the test (“Physics C”) is a calculus-based course that sticks to mechanics and E&M.
In my department, we used to allow students to test out of the first course of the introductory sequence with a 4/5 on the AP Physics C, and out of the first two courses with a 5/5. I think we may have let them out of one course for a 5/5 on the Physics B test, but I’m not even sure of that. I know that 4/5 on the Physics B test wasn’t worth anything. We’ve subsequently revised the curriculum to put some modern physics topics into the intro sequence, so these days all that AP scores get students is admission to the Honors section, which is being taught using a radically different approach.
My limited experience with students who got credit from their scores on the AP Physics C test is that they’re really about as well prepared as any of the students who come out of the intro classes. The sample size in this case is somewhere on the short side of 5, though, so I wouldn’t attempt to draw any conclusions from it. I only know one student who took the Physics B test, so I can’t say much about that. (“Know” in this case means “Know for sure that they took the test and got a good score.” I don’t see the high school transcripts of all of my students, so I’ve probably dealt with several AP graduates without knowing it.)
As for the specific misconceptions Prof. Camp complains about, that has nothing to do with the AP. The sorts of misconceptions he lists are the kinds of things tested by the conceptual diagnostic tests I talked about before moving to ScienceBlogs– I recognize “tables do not prevent things from falling by exerting a force but by simply being in the way” as a wrong answer from one of those tests, and my colleagues and I have chuckled over that one a few times. The thing is, most students leave college physics holding a few of those same misconceptions.
The average score on one of those conceptual pre-tests is something like 10/30, and the post-test scores for a typical lecture class only go up to about 15/30. A really first-rate “active learning” class can boost the average to something like 22/30. My students come in scoring a little better than the national average, and they leave doing a little better than the average for a traditional lecture course, but I still have students on the post-test thinking that objects move because of the force of their motion. (Of course, I also have at least one student a term who will say that the speed of light emitted by a moving object is something other than c. On multiple tests, even.)
This is hard stuff to learn, and really hard stuff to teach. I’m not in the least surprised that students leave high school AP classes with some serious gaps in their knowledge. Most students leave their college classes with some serious gaps in their knowledge, and they think less of us to boot.