Students Ryan (center) and Jakab (right) demonstrate their electromechanical marble sorter for judges from the U.S. Army Corps of Engineers Sacramento District during the sixth annual Folsom High School Engineering Challenge in Folsom, Calif., April 19, 2013. Looking on, from left, are district personnel Dan Holmberg, Jessica Morelli and Paul Risler. Photo cropped for emphasis. (U.S. Army photo by Robert Kidd/Released)