The Kaplan software, which simulates the actual exam, is very helpful for practice questions. It breaks down your practice exam scores so you really see where you need to focus. I would recommend buying this on its own, without enrolling in a course, which the quality of is very dependent on the individual instructor.
I found the best way to review specific subject matters was to go back to your textbooks that you used in those classes, organic chemistry and physics textbooks. These teach you to understand concepts, which is the most important factor to scoring well.