This summer as you're preparing for your physics courses, I'd highly recommend reading the Teacher's Manual for 5 Steps to a 5: AP Physics 1. It's a free download from McGraw-Hill. The framing device for the manual is "5 Steps for You to Help Your Students Get 5s." It discusses many of the specific approaches I take to my classes, all in the context of the AP Physics exam. Of course, these approaches are equally applicable to teaching any level of physics.
Integrated throughout the text are what I'd consider the Three Commandments of teaching... not just teaching physics, but of teaching high school at all. In the Teacher's Manual, I discuss these commandments with reference to beginning the course. But they apply equally to the AP exam review that many of us are deeply engaged with this time of year.
In case you're interested, Rule 2 is "Trust, but verify." Rule 3 is "Your students don't listen to you. (That's okay. They don't listen to me, either.)"
Rule 1: Never condescend.
When setting the tone for your course in September, it's important that your students perceive that they are being treated like adults. Yes, I understand that we are NOT officially teaching adults, and that some of our students will need intervention because their actions are not adult-like. Nevertheless, the assumption of good faith on your part will go an enormous distance toward earning cooperation from your students throughout the year. The majority of teenagers are, in fact, intellectually and emotionally ready to behave as adults. But this majority can be hypersensitive to perceived disrespect or condescension.
In the context of AP review: It can be quite disheartening during review time to see our students making the same danged mistakes that we've worked on eliminating -- especially when such mistakes are made by the particular students who spent part of the year hostile, or lazy, or arrogantly overconfident.
Nevertheless... there's little point in reminding students about their personal shortcomings right now. It's so tempting to say, "No wonder you're struggling. Remember all those poor homework assignments?" or "Now, you would remember the definitions of wave properties if you had paid appropriate attention in class." But do you really want to sound like a frustrated, nagging parent? Your student will tune you out the same way he tunes out his mom when she complains about how he never helps out around the house.
Just help the student, patiently. Or don't help -- it's reasonable to politely and respectfully point to the correct fact sheet or old homework problem: "John, before you try correcting this problem set, take a look at the wave definitions at the end of chapter 12. I think that'll put you on the right track." It's not your job to re-teach course material from scratch, but you should expect that even diligent students need reminders of things you studied earlier in the year.
It's not worth revisiting past failures in the runup to the AP exam. Just be glad that your student is putting forth some kind of effort now. Be respectful. Lazy students know they're lazy without you rubbing it in their face. And they're only going to change their future behaviour in response to a personal, internal decision to do so -- certainly not in response to a nagging physics teacher.