In regards to math as a college student, you ought to take a semester or two of calculus and, if it's convenient, a semester of statistics. Most science degrees require at least one semester of calculus, so you'll probably have to take it anyways (assuming, of course, that you opt for a degree in science). If you enjoy math and you're good at it, you ought to take calculus your freshman year. G.Chem, Bio, English, an elective, and calculus is a reasonable courseload for a freshman. You certainly don't want to couple calculus with organic chemistry your sophomore year. Be forewarned: ochem tends to brutalize students. The subject matter per se is not intellectually difficult, it just takes a long time to assimilate the material. Plus ochem lab is HELL. God I hated that lab with a passion. So my point is this: take calculus your freshman year, the first semester of your junior year, or as a senior.
Don't bother taking anatomy--it's pretty much a waste of time for pre-meds. However, physiology is a good class to take before the MCAT. Physiology is an MCAT favorite, so any prior knowledge of the subject is helpful. That said, don't feel like you HAVE to take physiology before the MCAT in order to ace it. I didn't take a physiology course before the MCAT, and I still earned a very competitive score. The physiology that is tested on the MCAT is very basic.
A few more nuggets of advice:
a) Take biochemistry your senior year.
b) Several of your electives ought to be in sociology (e.g., medical sociology), psychology, and anthropology (especially cultural anthropology).
c) Study abroad if you can--it's a wonderful experience.
d) Become proficient in spanish.
e) Do some research in a lab (at least a summer), because it will enrich your perspective on science. It will give you a much greater appreciation of scientific theory--the process of scientific inquiry is VERY challenging, tedious, and time-consuming.
f) Shadow some physicians. "Candy striping" is a waste of time.