Gavin Ohler, 10, of Arlington, won third place in LearningRx Nat’l President’s Day Contest, by reciting the U.S. Presidents in order while playing Hannon on the piano. The U.S. President recitation is a memory-enhancement exercise that helps LearningRx students increase their short-term and long-term memory. For more information, go to www.learningrx.com.