Joe Konieczny, who teaches in Georgia, writes in with a problem some folks would love to have, but a problem nonetheless:
This is my third year teaching AP Physics B and I'm at a new school with students who have already taken a year of Honors Physics (just switched from public to private school). The past two years my students have all taken the AP class as a first year physics course and so this year, three weeks in, I've yet to actually teach them something they don't know. I'm struggling to keep them challenged. How do you approach your AP students who have already seen a year of physics and keep them challenged?
Joe says he's "three weeks in" because in Georgia, summer vacation seems shorter than the lifetime of a muon.
Well, Joe, to be honest, I've never taught an AP B course in which ALL of the incoming students had taken physics before. And even then, the vast majority of those who have taken physics did so as freshmen. I just went at it as if it were a first year course, and everyone seemed happy.
The first step for you would probably be to evaluate to your satisfaction the scope and rigor of their previous physics course. Did all students take the same first-year course? Was it with the same teacher the whole way? Was the instructor competent? What topics did they cover, and how well do your students understand those topics? The first place to start, if possible, is to have a conversation with the students' previous teacher.
Next, right now in your current class, try getting into a topic they *haven't* seen before. Then you can get a sense of the students' true ability. Furthermore, depending on the topic, you might be able to see whether the students really understand what they learned last year. For example, maybe they didn't cover fluids last year. Dive in. (Hah!) See how they approach an Archimedes problem that includes equilibrium or Newton's third law. See how they handle a lab.
If your class truly has mastered the fundamentals of solving problems with Newton's Laws, energy conservation, and momentum conservation, then you can think of AP Physics B as applying those fundamentals in a variety of different topic areas, spending more time on the areas left uncovered last year. If, on the other hand, most of them keep saying things like "Wait, what do you mean, work done by friction?" then maybe the start-at-the-beginning approach would be better.
Regardless, by insisting on outstanding problem presentation with thorough explanations, it's likely that you can keep your strong students engaged, even if they think they have seen the material before. Setting sky-high expectations for problem sets is likely critical... if the students are acting unchallenged, then there's no reason they shouldn't be doing picture-perfect, suitable for framing in a museum, jobs on their homework. Perhaps you might think of last year's course as a wonderful head start, which could allow you to actually finish teaching all topics thoroughly in AP Physics B. This would make you practically unique amongst your peers.
Good luck. Let me know how things go, or if you have specific topics areas in which you want some feedback. It is *tough* to teach second-year physics when you weren't the first-year teacher.