I recently found out about the I Do Foundation, they allow couples to find ways to give back to charities through their wedding in 4 different ways.
Gift Registries that Give Back: Couples create gift registries on the I Do Foundation website and have up to 8% of gift spending donated to charity.
Wedding Favors for Charity: Instead of traditional favors couples can make a donation in honor of their guests.
Charity Registry: Couples can encourage their guests to support their favorite charities by creating a registry for charitable donations.
Shopping for Change: Couples can raise donations through their invitation, jewelry purchases and honeymoon.