Crystal Brockington and Aaron Barron, both 18 years old, designed a more efficient and cost effective solar cell that harnesses energy without cadmium, which has been shown to be harmful to the environment. They were selected to participate in the White House Science Fair after they were awarded the High School Grand Prize at the Siemens We Can Change the World Challenge. The fourth White House Science Fair was held at the White House on May 27, 2014 and included 100 students from more than 30 different states who competed in science, technology, engineering, and math (STEM) competitions. (Photo Credit: NASA/Aubrey Gemignani)