After approximately 30-40 seconds of moderate rubbing together of hands, compare the heat level on the hands of the two groups. Use or construct rollers sufficient to carry a weight of 10 kg. Attach a small spring scale to the weight and have students measure the amount of pull that is required to move the weight across a carpeted area. Repeat the experiment with the weight on a wooden or tiled surface and finally, do the experiment with the weight on rollers. Discuss why there are differences in the scale when the object is pulled on the different surfaces.
Discuss die use of bearings and hinges as methods of reducing friction.
Have students examine or research ball bearings. Examine the design of a canoe and a toboggan. Have students discuss the impact of the design on friction. Have them compare the efficiency of a loaded toboggan and a loaded sleigh with runners on snow. Have students research and discuss the properties of ice as a friction-reducing agent.