Our youngest son Levi recently won 4th place in his school's science fair. He constructed a Rubens' Tube which actually shows sound waves. The little black thing on the left is a speaker, and when this picture was taken, there was a 480 megahertz tone being played on it. You can actually see the sound waves! When regular music is played, the flames bounce up and down, getting higher with the louder sounds and lower with the softer sounds. This has been my favorite project yet. It is much quieter than last year's project -- a racing mower.
