Wintergreen Motion Discovery Tubes

Our clear-view tubes are a fascinating way for kids to get hands-on experience with friction, flow and speed! Each tube is designed to showcase a different aspect of motion-children simply flip the tubes and watch as the angle of a track determines the speed of the balls, the size of a funnel controls flow...and the smoothness of the tracks controls how fast or slow the balls move! You get a set of 3 permanently sealed tubes; each measures 13 1/2".