Donation centers do not give money back for items (at least none that I'm aware of). At most, you get a receipt for tax purposes.

OUaC is a consignment shop. You can sell your gently used items to them or trade them for stuff they're selling.

And they do NOT cater to the poor. Trust me on this. They generally only take higher-end children's clothes (Gymboree, Gap, or above), usually set up shop in more affluent areas, and sell the items at fairly high prices. (That's what other mothers have told me, at least. They've said for used items, the prices are pretty high - but still a little lower than what you'd pay new.)