Third Graders Experiment with Force and Motion

The third graders have been learning about force and motion in various ways.  Today we performed 2 different experiments around force and motion.  The first was with a small catapult.  We launched a pom-pom off a catapult, two trials having the catapult halfway down and two trials having the catapult all the way down.  We measured how far the catapult launched the pom-pom each time.  The second experiment was with a pulley and a scale.  We used a pulley system to fill a jar with marbles and weigh different amounts of marbles inside the jar.  We observed the pulley and noticed the changes as we added more marbles.