Futile TUTORING! Please read on...
I've had two chemistry classes: one in high school and one in college (level 1111, we use four digits here; it is probably something to the effect of a 101 level for those who use three digits). In neither of these were we taught about anything of the sort of quantum levels--we just learned basic atomic structures, how they correspond to the specific element, and a very mild understanding of how chemical and ionic bonds work, and the differences between them. I'm not quite sure why it would be necessary to teach them any advanced physics about it; it might just make their brain explode.
If I were you, I'd persue the chemistry teachers about the chemistry cirriculum and ask them what to do about it.
P.S. $80 USD for an AP test? Yikes! They were free at my high school here in Minnesota.