First of all why are you taking calc based physics? calc based physics is good but not the one you really need for MCAT and beyond. MCAT will test on trig based physics and medical schools do *not* require (although maybe some do but they are in the minority) calc based physics. If your school only has calc based physics that is another issue. Have you had calculus? is this not a requirement for this class? if you have problems with concepts I can suggest a good book but if it is the math that is getting you into trouble then I suggest getting a math tutor and brushing up..