I spend the first half of the term studying like crazy until I know everything the book can teach me. Then the second half is all much easier - looking over notes, doing assignments, working practice problems, the works. Just enough to keep sharp. Works pretty well for me!
Until last term, though, I'd outline the chapters as they came up, rewrite my class notes (combining them with my book ones), do practice problems only on the current unit, etc. I worked way too hard all term and burnt out after finals. I mean, I seriously would take a week off work and all other responsibilities to just rest.
There are some classes that my new method doesn't work as well for (foreign languages, anyone?), but it can be adjusted.
So. First half of the term: 5-6 hours per day.
Second half of the term: 1-2 hours per day, if that.
Pretty handy!