Explore and Play: Switch Directions

Send a ball down a ramp, hit an obstacle, and make it change direction. 


  • large marbles
  • ramp materials, children’s choice
  • masking tape
  • scissors

Key Science Concepts

  • When a rolling or sliding object hits an obstacle, it will stop or slow down and its direction may change.
  • When a stationary object is hit by a rolling or sliding object, the force may knock the object over or cause it to move depending on how fast the moving object is going and how heavy it is.


Challenge children to build a ramp that causes a rolling or sliding object to hit an obstacle and then change direction. They can use any of the ramp materials—flat ramps, tubes, or flexible ramps—to build their ramp. 

Reflect and Share

Ask children to explain how their ramp constructions work. What problems did they run into and how did they solve them?  Did they test how their ramp worked?  If so, did testing help them figure out how to build their ramp so it worked the way they wanted it to? How?