Hillsboro boys hadn't turned out for the National Soapbox Derby contest. The older boys whose age made them eligible to enter just didn't take an interest. But, from the time Vio spotted the official wheels of the Derby stacked in his grandfather's hardware store, he was anxious to try his hand at building a car for competition. The author has faithfully charted the rises and falls in a boy's enthusiasm for a big, complicated project. Vic's car is for a local contest but the rules are the ones applied by the National Soapbox Derby. He has to do and make everything himself and his own manual clumsiness brings him to the verge of dropping out. There is an older neighbor who stops in to jeer at his efforts and ruin his morale. Vic sticks with it through an exciting and rewarding competition day. The story will carry boys while the information about the Derby and car building methods will inform and possibly inspire imitation.