I seldom carry a bag to school. I have numerous bags, but I tend to not carry them back and forth. I can work on the computer either place, with google docs or dropbox. I have my textbooks or whatever to work with on campus. Once in a while a book will migrate from home to campus and viceversa, but I have little need to take work home, aside from the work that already is home.
I'm trying to go as paperless as I can. Most of office mess is either papers or books, and the books are enough. I'd love never to have to touch a loose piece of paper again in my life, if it isn't a grocery list.