Hannah Doerksen-Goldwater (center) and Kayle Watson, both 12-year-olds from Corning, N.Y., talk with Rep. Tom Reed on Thursday about a nanotube model that is part of their RadiClear filtration system, which is designed to separate radium from water. Their winning exhibit is part of 20th anniversary of the ExploraVision K-12 science competition sponsored by Toshiba and the National Science Teacher Association.