Set up a basic solid, smooth and rigid material, such as wood or plywood, ramp against a chair, on top of some books, or from a table to the floor. Hold the car at the top of the ramp, and release to demonstrate the two main kinds of energy. Potential energy is placed into the car when it’s lifted from the floor, and that energy is released as the car rolls down the ramp.


Using the ramp, drop the car from the top of the ramp again, and measure how far it rolls this time. Now, place a sheet of card stock at the bottom of the ramp, and let the car roll over that. Measure the distance it rolls. Place some sandpaper on top of the card stock, release the car, and measure that distance. Finally, try it with some carpet at the bottom.


Place a heavy stack of books a few feet from the end of the ramp, so that the car hits those books when it rolls from the top down. Demonstrate that once or twice, and then take a small ball of clay or putty. Place it on top of the car and pat it down slightly so it won’t roll off. Roll the car down the ramp, and test Newton’s first law of motion: anything moving is going to want to keep moving (until it crashes into a wall).


Race two cars from the top of the ramp. Place a line of masking tape on the floor a few feet from the ramp, so it acts as a finish line. Release them and see which one goes the farthest and the fastest (using a measuring stick and a stopwatch). Now, try to make each car faster. Scientifically test these changes.


Motion may seem like it’s a one-way street, but more advanced science gets into things called vectors, which are used to plot a direction on a chart. To demonstrate one, place a piece of newspaper, plastic, or cardboard on the table (you may need to make a rope handle so you can pull it easily without wrinkling it). Roll a car slowly across the plastic, then start pulling the sheet out from under it. The car’s forward motion combined with your pulling should make the car move diagonally along a combined vector of both.