Seconding this great advice. You'll regret it if you get stuck on a course you hate. Good professors want you to succeed (if only for their student evals ;) ) and will do what they can to help their students do so. Those participation grades can be a pain but they care more about quality than quantity; if you don't say that much in class, but your responses are generally considered and thoughtful, you're gonna get a better grade than the students who blather on and on.