The Summer Games will be held from July 27-August 12.
In celebration of today's announcement, Mrs. Obama held a "mini-Olympics" event at American University for local Washington D.C. children.
In partnership with first lady of Britain, Samantha Cameron, Mrs. Obama invited. U.S. Olympians Dominique Dawes, Lisa Leslie and more to participate in the "Let's Move" event that also doubled as the Summer Games unofficial kick-off.
As tradition would have it, Mrs. Obama follows in the footsteps of so many First Ladies before her -- Laura Bush led the U.S. delegation during the 2006 Winter Olympics in Italy and Hillary Clinton did the same at the 1994 Winter Olympics in Norway.