Will my hot chocolate cool down faster if I add the cold milk now or later? Will ketchup flow faster if it's stirred first? Taking first place in the science fair has never been so much fun! These biology, chemistry, and physics experiments, devised by a real scientist and former high school chemistry teacher, really rock. That's because each activity answers questions that actually fascinate kids--whether they're exploring the laws of motion by smashing eggs against a wall, learning how to use diapers to prevent fire, or going "Supersonic" as they measure the speed of sound. Also, there's great advice on designing your own experiments, catching errors that could affect the results; and presenting the project so that it will impress the judges.