What to do with all your school notes after you graduate

Besides burning them, what other more environmentally friendly (and potentially less hazardous in urban areas) options are there?

Apple on Desk. Photo by JJ Thompson on Unsplash.

The real reason we have school

Does anybody remember how to do quadratics? Me neither, and I'm doing it right now. If school isn't about learning subjects to use in our future careers, what is is for?