Try Donorschoose.org

Donors Choose was started in 2000 by a teacher at a Bronx public high school as a way to  provide much needed educational supplies to his classroom. You choose which projects you want to support, and you can even narrow your search to a specific area or school; projects range from providing books and art supplies to class trips. The requested items are purchased by Donors Choose and sent directly to the classroom. You will receive a thank you note, and photos from the classroom you helped. Check it out today!