Paddle Boats
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Plastic water bottle or soda bottle with a cap
Wooden skewers
Rubber bands
Cardboard
Duct tape
Scissors
Construction
1. Make sure the plastic bottle is capped tightly so that water will not be able to get inside your boat.
2. Take two wooden skewers of the same length and tape one to each side of the bottle. Make sure that the
skewers stick out past the end of the bottle.
3. Use scissors to cut out a rectangular cardboard paddle that will fit between the two skewers without
touching them.
4. Water proof the paddle with duct tape and then wrap a rubber band lengthwise around the paddle.
Secure the rubber band with tape. Finally, stretch one end of the rubber band around each of the skewers.
Skewers
Paddle
Bottle
Experimenting and Trouble Shooting
1. Fill a tub or kiddie pool with water. Now your boat is ready for testing! Wind the rubber band paddle,
place your boat in the water, and let go. What happened?
2. Pour a bit of water into the bottle to add some weight to the boat. How does this affect the motion of
the boat?
3. Are the skewers bending when the rubber band is wound tight? Experiment with the placement of the
rubber band. Can you get it closer to the bottle? Can you reinforce the skewers some how? Try adding
additional skewers for support and strengthening them with tape.
How It Works
Your boat moves by changing stored energy, or potential energy into motion energy, or kinetic energy.
Winding the rubber band creates stored energy. The tighter you wind the rubber band, the more energy is
being stored. When the rubber band is let go, it quickly unwinds and propels the boat forward as it
converts the energy into motion.
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