One term in high school I put a laptop bag strap on a hanging file box and used that as a bag for a semester. It made me nuts that teachers hand you stuff you need to hold on to that has no holes in it, but you're supposed to store it in a 3 ring binder. Everything you are supposed to bring with you to class is the shape of a rectangle, but a backpack is a blob that lets your stuff fall to the bottom. Best grades I ever got. Ended up hurting my back so I went back to a backpack. I got a lot of "why don't you just…" questions for a day or two and then it was chill.

This bag shape seems far superior for the purposes of carrying paper hither and thither than any other bag shape I've seen.