Boys and Girls club. Ask bike shops if they know of a "Bike Kitchen" in your neck of the woods. (they teach kids how to fix/maintain bikes on a donated bike that the kid then gets to keep) Battered women and children's shelter. Food bank. School clothing bank. (most school districts around here seem to have one, where kids can get school clothes and supplies)
At the very least, put it out front of your house with a "free" sign on it. My housemates and I did that once, then went to the grocery store. When we came home we saw an ecstatic teenage boy riding the bike around the neighborhood. Obviously he'd fixed it and got it rolling right away. He was grinning ear-to-ear. It was awesome.
"If Americans want to live the American Dream, they should go to Denmark." - Richard Wilkinson