Kids explore motion, friction, cause and effect, and more—with a 2-lane activity ramp that brings STEM concepts to life! Children just place a textured path on each side of the divided wooden ramp…then compare how the different textures affect the speed and momentum of rolling objects. Great for use with toy vehicles, balls and more, the ramp includes 6 rugged plastic paths. Ramp measures 16" in length; each lane measures 3 1/2" wide. Cars sold separately.