I am attempting to raise money for One Laptop Per Child, and I was wondering about giving receipts?

If they are donating via you also not directly on a 501(c)3 organization, their donation isn't tax deductible. What you might do is have them make checks out on the OLPC organism and enthrall them all in, claim OLPC on provide receipts directly to the donors, then they would be deductible since OLPC is a 501(c)3 organization. The receipts would come from OLPC, not coming out of you. You could write them a finicking letter appreciating them because donating, but that isn't a tax deductible receipt.