What should I do with my spare binders and folders?

I have a bunch of binders, folders and lever arch files left over from my school days and university. Most of them are still in GREAT condition but I just don't need them anymore and I doubt they would fetch anything on eBay considering postage costs, so what can I do with them? I don't want to throw them out, that would be a complete waste. I have a local Oxfam store but I don't know if Oxfam would accept stationery and stuff like folders. Help?