Bring a tornado into your classroom! This apparatus allows you and your students to create a small vortex that simulates the vortex of a real tornado. Explore the dynamics of tornadoes, the factors that allow a vortex to form, and more. Includes: 2 pcs. plexiglass, 2 sides painted black, lower base with legs, upper frame with fan, plastic bowl, instructions with background information and suggested experiments. Required but not included: 9-volt battery, dry ice, ultrasonic humidifier.