Serena Williams was among the athletes who joined First Lady Michelle Obama in Chicago on Thursday to help launch her "Let's Move! Active Schools" program, which promotes physical activity for students.
San Francisco 49ers quarterback Colin Kaepernick, U.S. Olympic gold medalists Gabby Douglas, Dominique Dawes, Allyson Felix and Ashton Eaton and former NFL and MLB star Bo Jackson also participated in helping Obama lead a reported 6,000 schoolchildren in a midday workout.
Check out some pictures from the event after the jump.
(All photos via Reuters)