I took AP Calculus BC my junior year in high school, and like the first poster said, it's just the next step up. It's not really like you have a choice between taking AP Calc and regular calc... calc is calc, and yes it's hard, but so was algebra when you were learning it. i think ap gov is a pretty fun and easy class (but it does depend on your teacher), but definitely don't take it if you're not good at memorization, because that's basically all it is. also, if you're not into it, you're going to HATE the class, so don't just take it for the extra grade point. as for the course load, it depends on the person, but you should be fine. i took ap calc, ap english, ap physics, and ap us history all in my junior year, and ap stats, ap english, ap gov, and ap spanish my senior year, and i maintained a high grade point average. if you don't think you'll be willing to study, don't do it, especially since it's your senior year. good luck in whatever you decide!