This rugged, compact device allows students to clearly visualize and quantify projectile motion. A steel ball is launched repeatedly from the same place on a ramp and strikes a recording paper on a target plate that is moved horizontally each time. As each of these marks is transferred to the background graph paper, the shape and properties of the trajectory emerge. This provides a wonderful opportunity to study a body that is uniformly moving horizontally and uniformly accelerating vertically. The ability to separate motion into components is crucial to Supplied with a steel ball, 5 sheets of graph paper and special recording paper for use on the target plate.