The candle clock was used years ago to indicate the passing of time. Special candles were marked with lines spaced so that, as the candle burned down, one line would disappear each hour. The process of marking the lines is called calibration. In this activity you will calibrate a candle to make a candle clock.
A. Plan the activity a few days ahead as it might take most of the day to complete. AND plan a strategy to convince the principal to use your candle to run the school for a day.
B. Decide what marks you will make on the candle. You might choose, for example to make marks for 15-minute periods of time. Thin candles burn faster than thick candles.
C. Place the candles firmly in the holders.
D. Put the candle holders close together and check that the candles are the same height.
E. Light one candle. After the chosen period of time make a mark on the second candle opposite the top of the burning candle. Carry on marking the second candle until about one third of the candle has burned.

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