This unique device allows students to plot the trajectory of a projectile. A steel ball launched from a ramp hits pressure-sensitive paper on the vertical target plate. The contact point is manually recorded on the backboard graph paper. The target plate is moved to different positions within the ball's flight path and the exercise repeated to generate the full trajectory of the ball. Consists of a 36 × 43-cm plotting board, 2 wooden supports, an adjustable aluminum launcher with a stop, an aluminum target plate, steel ball, graph paper, and marking paper. * Instructions included. *