Physics really is "phun"
Third-, fourth- and fifth-grade students at West Elementary School in Colorado Springs, Colo., observe how liquid nitrogen affects a balloon during a "Physics is Phun" event held at the school Dec. 11, 2009, by members of the Air Force Academy's Physics Department. "Physics is Phun" is an Academy education outreach program to show children how fun physics, science and mathematics can be. (U.S. Air Force photo/Julie Imada)