Another site from Marylaine Block:
"DonorsChoose.org - an online charity connecting you to classrooms in need
Teachers often have wonderful, hands-on learning projects that require a little money up front - and these days, that money is hard to come by. Teachers can explain their projects here, along with their projected cost, and anyone who'd like to contribute can choose which projects they'd like to fund. You can also read about how completed projects funded here worked out."