The pitcher throws the ball and the batter takes a mighty swing. Crack! The ball is hit on the sweet spot and soars to the outfield. Or, you hear a thud! This time, the ball dribbles along the infield ground and the batter's hands sting. Everyone who has played baseball or softball has probably experienced both of these outcomes. This may not seem like science, but it is a lesson in frequencies of vibrations and transfer of energy: "For most engineered sports equipment, energy transfer is the single most important scientific concept" (University of Colorado, 2006, p. 1). This article describes an inquiry-based lesson in which students investigate the sweet spots of sports equipment and discover how engineering impacts everyday life. (Contains 5 figures, 1 resource, and 2 online resources.)