President Barack Obama watches as Thomas Shields, 13, left, and Rush Lyons, 14, right, both from Theodore, Alabama, demonstrate their robot 'Vator', which was designed to mimic a space

 

              President Barack Obama watches as Thomas Shields, 13, left, and Rush Lyons, 14, right, both from Theodore, Alabama, demonstrate their robot
President Barack Obama watches as Thomas Shields, 13, left, and Rush Lyons, 14, right, both from Theodore, Alabama, demonstrate their robot 'Vator', which was designed to mimic a space elevator, Monday, April 22, 2013, at the White House Science Fair in the State Dining Room of the White House in Washington. (AP Photo/Pablo Martinez Monsivais)