It depends on the classes you take. The good thing is that you can schedule your classes to be later in the day. Also, you don't have to take 7 or 8 classes like you do in high school. If you want to be a full time student you have to have 12 hours of class a week, or 4 classes.
You can also look at your schedule and read or work ahead of time.

During midterms and finals, students don't get that much sleep.