Did you know that a Slinky makes a handy model of earthquake waves? In this activity, learners use one or two of these simple toys to illustrate the different kinds of waves that transmit the energy of an earthquake outward from its epicenter. Move the slinky back and forth and create seismic primary waves, or P waves. Shake the Slinky up and down and notice a different type of wave traveling along. This activity requires two people.