Students used cylindrical bottles and cans, rubber bands, paper clips and various "drive shafts" (pencils, popsicle sticks, chop sticks, etc.) to create self-propelled cylinder racers. Each group is working to overcome problems related to friction, power (too little or too much), imperfect cylinders and "blown engines". Eventually groups will compete in drag races, distance races, uphill races and the ever-popular demolition derby.
