What science class should I take my senior year of high school?

I would take physics. The physics you take in college to meet the prerequisites usually assumes you've had some high school level physics. It can be a challenging course...especially if you haven't had it before. It requires a lot of math, and if you are not practicing that skill, it's easy to loose. The general anatomy class you will take as an undergraduate can really be taken at any time and requires no prior exposure to anatomy. I think anatomy is pretty easy to pick up...it's just a lot of memorization and visualization. So, I would just take this in college.