Take the children outside for this experiment. Poke a hole on the side of a Styrofoam cup with a pen or pencil, and have each cover the hole with his finger. Pour water in each of the cups. Allow the children to hold up the cup and remove their fingers so the holes are exposed and the water flows out. Next, refill the cups while the children are once again covering the holes. This time, have them drop the cups while carefully watching the holes. They’ll be able to see that as a cup falls, the water does not leak out of the hole. This is because as the cup is falling, the gravitational pull on both the cup and water is equal. Because the water and cup are descending at the same speed, there is nothing forcing the water out.
Have children hold out their arms perpendicularly while holding an orange and a dime. Then, tell them to drop both the objects at the same time. They will see that although the orange and the dime have different weights, the gravitational pull on the objects was the same and they will land on the ground at about the same time. Next, have the children repeat the experiment, but this time hold a piece of paper instead of the dime. They will note that the orange hits the ground much faster than the paper. The paper’s size and light weight interfere with the gravitational pull. Some objects, such as pieces of paper, parachutes and feathers, seem to defy the laws of gravity and are buoyed by the gases in the air. However, if the children were to drop the objects where there were no gases in the air, they would fall at the same speed.
Have your children stand against a wall with their feet together and the backs of their heels touching the wall. Place an object about 20 inches from the wall, and ask the children to try to pick up the object without bending their knees or moving their feet. They won’t be able to complete the task without falling over. This is because their center of gravity is over their feet. When they bend over to pick up the object, their center of gravity moves forward, so they must move their feet forward to stay balanced.
Have the children construct a parachute to help them witness firsthand how an object can resist gravitational pull. The parachute can be constructed from a piece of paper or a plastic bag and string. Cut the paper or bag into an octagonal shape, and punch eight holes around the edges. Thread a piece of string through each hole. Tie the pieces of string to a weight, such as an action figure. Have the children drop the parachute from a high place, such as a balcony. They can watch as the parachute floats slowly to the ground due to air resistance.