I'm just starting out teaching in a US high school, and I have AP Physics B that I'm taking over in the Spring. I've never taught physics before except in a tutoring context. All my students are seniors, and are taking 7 classes total! Each of those classes meets 4 times per week. So I can't just go wild and assign 30 problems every night. The total amount of time seniors spend on homework for all their classes needs to be about two hours a day. And the last piece of background info you need to answer my question is that, generally, I'm planning on doing a very short lecture in class (say, 10-15 minutes), followed by the students working on their "homework" sets in class, with me walking around and helping individual students. So they will have 35-40 minutes to work on their problem sets in class. I'm planning on collecting homework every day, except for quiz and test days. Given all this info, what do you think is a reasonable number of homework problems to assign each day? Thanks in advance for your help!