S5·E7 Downhill Racer

George loves cars And when he hears about the annual Soap Box Derby race in the country, he and Allie decide to enter. But first, they need to build a car, and the rules say no help is allowed. So they look at a book that shows them the parts they need to build a soap box derby racer and find out just what is needed to make one go downhill, and stop.