One fun way to use science in summer projects is to do puzzles. Today we used a little chemical reaction to create a vacuum and obtain a coin without getting our fingers wet.
The set-up for this puzzle is easy. All you need is a pie pan, some water and a coin. Fill the pie pan about 1/2 to 2/3 full with the water and put the coin in the pan. The challenge is to get the coin without getting your finger wet. Also present is a jar (such as from jam - but we used a beaker) and some paper towels. The paper towels are there to solve the problem, but also help to distract the puzzle solver. The idea that the water could be soaked up with the towels could be tried, but you have too few towels to do the trick. Once the person gives up, you do a little chemistry and get the coin.
To get the coin, take a piece of the paper towel (probably 1/3 to 1/2 a sheet is plenty) and put it inside the jar. Take a lighter (or a match) and light the paper on fire in the jar. Let it burn for a second or two. Take the jar, turn it over and put it in the water in the pie pan. The fire will go out quickly but it will have gone on long enough to use up some of the oxygen in the jar - creating a vacuum. The water is sucked up into the jar and the coin can be picked up without getting your fingers wet.