Make your own soap powered boat!

Materials

•     Cardboard
•     Left over bar soap
•     Dish Liquid
•     2 or 3 Tub for water
•     Scissors
•     Water

Activity

1. Using scissor with adult supervision cut out different size boat shapes from the card board. The back of the boat should be flat and the front of the point should be slightly pointed. Cut a small notch into the back of each boat.
2. Fill the tubs with water.
3. Place the boats into the water. What happens? Take the boats out of the water.
4. Use the scissors to make some sliver of soap. The slivers should fit into the notch on the back of the boat. Place the soap into the notch and then place the boat into the water. What happens?
5. You can repeat the experiment using dish liquid instead of bar soap. Instead of placing a sliver of soap into the notch, squeeze a drop of dish liquid into the notch while the boat is already in the water.
6. Make sure to use fresh water between experiments. Once soap has been introduced into the water the soap boats become less effective.

Taking it further

Not only soap boats fun, but they can be used to illustrate and learn about science.
    Why does adding soap to water make the boats move? It’s because of what water is made of. Hydrogen and Oxygen (H20= water) bond together very strongly. That is why water has so much surface tension (and why it hurts so bad to do a belly flop). To test the surface tension of water put some water into a bowl. Try floating different objects on it. You can float a paper clip by gently lowering it into the water on the end of a fork. Now, to see how the soap affects the surface tension shake some pepper onto the surface of the water. Use enough that you can easily see the pepper floating all over the water. In the middle of the water add just a drop of soap. The pepper will zoom away from the center and some of it will sink. That is because the soap gets in between the hydrogen and oxygen atoms and breaks up the surface tension.