Tips for time management in college

I'm in a rough spot right now.

I've just started college away from home in a fairly tough computer engineering program. I'm trying to find time for my girlfriend, my school work, exercise, and personal projects. But it seems impossible with my dorm mates staying up late and the life-consuming calculus and natural science courses I have to take for freshmen year.

For those of you who've made it through similar programs, how did you balance everything and still come out with good grades?