Carl Engwall, South Dakota Air and Space Museum director, gives fifth graders a tour of a missile alert facility exhibit during a STARBASE visit at the South Dakota Air and Space Museum, Feb. 11, 2011. STARBASE is a Department of Defense program designed to raise interest and improve knowledge and skills of at-risk youth in science, technology, engineering and mathematics. (U.S. Air Force photo/Senior Airman Kasey Close)