Cut out a paper rocket and attach a straw then thread onto a string. Use your breath to blow the rocket along the string (can have timed races). Then attach a balloon on another straw and see how much quicker the rocket travels.
Paper, scissors, string (with used a variety so the Cubs could investigate whether the rocket travelled better using wool, kite string, leather string or thin ribbon). Straws (wider ones are better to thread through). Balloons. Cellotape
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