50# of books!
We just converted to all electronic and every student gets an iPad. We keep every single lecture slide for the whole programme online so the students can access any slide from any lecture from all 4 years at any time.
I understand that all places haven't converted but even when I was in undergrad a wee bit ago, I never had 50# of books and even when I had some books, I never carried them around ... I usually went to class with a few scraps of paper.
Why haul the books?
edit: FWIW, I fit all of my daily needs in a 20L rucksack which includes food, rMBP and change of clothes (wallet, passport, mobile phone, keys etc...) it just sounds like you're hauling too much stuff around?