For her science fair project, Shannon wanted to build five motorboats and race them to see which construction material would be fastest. The five materials she wanted to use were paper, cloth, aluminum foil, wood, and plastic. But we could not figure out a good way to get the paper and cloth boats to float. Waxing them would make it impossible to hold their shape. So we decided to get rid of those two boats. The aluminum foil one was also very hard to keep floating, so Mei-Ling suggested replacing that with a rectangular tin lid.

For the plastic boat, we cut a SunnyD bottle in half, taped the two halves together, and closed off the cap opening. We built one wooden boat out of a kit purchased at Michaels, with additional pontoons added by drilling 3/4" holes into a dowel, with the ends capped. A second wooden boat was also introduced by Mei-Ling: an old marker holder.

To keep the boats moving along a straight line, Shannon and I each held one end of a thread slipped through a straw attached to the side of each boat. Without this, the boats would tend to go in circles as there were no rudders and the propeller is angled.

The results of the experiment were that the rectangular metal lid went fastest. This is even though the plastic boat was the lightest. The wooden boats were very heavy, and the motor and propeller were barely able to move them.

After all of this was done, Shannon and I put together her poster. The science fair is on April 11.

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