I have started getting rid of old notes and papers from college and grad school. If I haven't looked at them in over 20 years and I don't even remember the class they came from, it's probably safe to recycle them now. I may keep a few souvenirs, though, like my Bio 1/2 lab notebook. Also my binder from my senior year directed reading. It was in a field that I now work in and it amuses me that I now collaborate with a number of people whose work I was reading then when the world of research was elevated and mysterious. Now I know where the sausages come from.