Sixth-grader Rufus Mayflower doesn't set out to become a millionaire. He just wants to save on toothpaste. Betting he can make a gallon of his own for the same price as one tube from the store, Rufus develops a step-by-step plan with help from his friends, classmates, and math teacher. By the time he reaches the eighth grade, Rufus makes more than a gallon - he makes a million!