(Grades 5th-12th) Demonstrate the relationship between speed and kinetic energy by dropping a ball from two different heights onto a bed of soft clay. For the second drop, the ball is traveling twice as fast, and it forms a crater four times as deep, indicating that it has four times the energy. After the demonstration, the clay can be removed and cut in half along the crater marks to measure and compare the depth of the craters. Includes instructions and student worksheets. All materials are completely reusable.