Usher, Mary J. Blige, Gwen Stefani, Common and Train are scheduled to perform Saturday during the free event hosted by will.i.am and Soledad O'Brien. The rally runs from 11 a.m. to 7 p.m. near the Washington Monument.Earth Day organizers also are announcing plans with developers of the popular "Angry Birds" game to create a new in-game experience about climate change. "Angry Birds" has been downloaded 2.8 billion times worldwide. The game's climate change campaign will coincide with the U.N. General Assembly in September as world leaders tackle sustainability goals.
Earth Day Network President Kathleen Rogers says the game and celebrity power will help more people focus on solving climate change.