(Mt. Bethel, PA) -- The musician behind many of the great "Schoolhouse Rock!" songs is dead. Bob Dorough passed away Monday at the age of 94. Dorough may not be a household name, but his songs helped young people across generations navigate the complicated worlds of grammar, math and science. His best known piece from the animated musical series is arguably "Conjunction, Junction," but Dorough was also behind all the songs in the show's "Multiplication Rock" series. Dorough also excelled as a jazz pianist, working with the likes of Miles Davis.