Check out the reddit reddit 2012 Gift Exchange, which is putting books in classrooms! Registration ends tomorrow, March 5th. Here's more about it:
We know how good it feels to give someone a book they have always wanted to read or one you think they will love. Now imagine how much better it will feel if, when giving a book to a fellow redditor, you also make a donation to DonorsChoose.org! We have a page at Donors Choose where you can pick any book related teacher request that you see fit. Upon signing up for the book exchange, you will receive a special code and, when you enter it on DonorsChoose.org, they will DOUBLE your donation up to $1,000! Donations aren't required but we really hope you will donate!
I learned about the exchange from Amber Benson, who is one of many awesome authors supporting the exchange.
reddit: Books are awesome. Check them out.