Making a Quarry Shot
Cut the aluminum foil into small squares about the size of a quarter (approximately 15 pieces altogether). Drop the pieces into a tall glass jar. Have an adult fill the jar with boiled water. Add 3 tablespoons of washing soda to the water. With an adult’s assistance, let the children cover the top of the jar with aluminum foil and fold the foil around the rim to make a tight-fitting cover. Using a sharpened pencil, poke a small hole in the center of the foil. Watch closely as the foil pieces magically rise to the surface and bubbles form. After two minutes, hold the end of a lit birthday candle directly over the hole in the foil and wait for the noise.
After each "explosion", readjust the foil for a snug fit. Don’t be alarmed if a flame appears over the hole. The flame and the pop are caused by the combustion of hydrogen gas. The hydrogen gas was created by the reaction between the aluminum foil, washing soda, and the hot water.
After awhile, have the children remove the aluminum foil lid and pour some dishwashing liquid into the water. Stir the detergent into the water and place a lit candle over the bubbles. Watch the amazement of the children as the candle is extinguished.