* Dorothy Canfield Fisher Children's Book Award *
In this award-winning story, two classmates set out to create affordable toothpaste and become accidental millionaires!

Sixth-grader Rufus Mayflower is betting that he can make a whole gallon of toothpaste for the same price as one tube from the store. There’s just one problem, he has to solve real-life mathematical equations first! With help from his good friend Kate Mackinstrey, can these two entrepreneurs keep up with the high demand for their popular product? Beloved children’s author Jean Merrill introduces readers to the ins and outs of a budding business, from costs to profits, in this exciting tale about perseverance, ingenuity, and underdogs.