Get old inner tubes from a company that sells truck tires. (Car tires are mostly tubeless these days.) Stage a tube race by having contestants sit on the tubes and try to make them move. Touching the ground directly with feet or hands is not allowed.
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Get a 10-by-20-foot sheet of plastic from a hardware or builder’s supply store
(about $4.50). Unroll it on the ground, flood it with water from a garden hose, and