Magic See-Saw


paring knife
10-inch candle
2 saucers
2 identical, tall drinking glasses
2 strait pins
adult helper


1) Have adult use the knife to remove about an inch of the wax from around the bottom, revealing the wick.
2) Use the ruler to find the center of the candle as best you can. Make a small mark in the wax with your nail to make it easy to find again.
3) Push one pin into each side of the candle at the center.
4) Rest the pens on the rims of the two glasses. The candle should balance, if one end tips down further than the other, ask the adult to trim the wax on that side until it balances. When you have it balances horizontally, it should rock very easily like a seesaw.
5) Place the one saucer under each end of the candle. Then, using the matches, ask the adult to light the candle at both ends.
6) When you are finished observing, remember to blow out both ends of the candle.

Explanation: When you light the candle, the heat of the flame melts the wax from solid to liquid. The end that the adult lights first starts to melt first, and some runs off the candle and onto the saucer. This makes the first end lighter, so it rises up. When the second end is tilted down, the flame burns closer to the wax. The melted wax then drips off that end faster, making it lighter, so the first end is lowered again.

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