Beyonce, Tina Knowles, and their family fashion brand, Dereon, teamed up with the first Lady Michelle Obama, as the t-shirt sponsor for the "Let's Move! Flash Workout" campaign. Beyonce's song, "Move Your Body," is also used in the campaign. The goal of the campaign is to encourage young children to make healthier lifestyle choices. Beyonce surprised students yesterday at PS/MS 161 in Harlem. You can see a video of Beyonce surprising the school kids here. Michelle Obama also surprised kids at a middle school and danced to Beyonce's song.