Operation Santa is in full swing at U.S. post offices across the country.
Operation Santa is now in its 100th year. Basically, needy families write letters to Santa and anonymous donors help fulfill their requests.
People of all ages write letters to Santa: some are children, while others are parents.
To commemorate the 100th anniversary of Operation Santa, the postal service has issued a special Santa stamp and is selling memorabilia, including a holiday ornament and a children's book.