In the 1950's, when Danny Dunn was a young boy, it was extraordinarily unusual to have a computer at home or at school. In fact, personal computers hadn't even been invented yet! But when Professor Bullfinch leaves for Washington and entrusts Danny with the care of his computer, Danny gets the bright idea of using the computer to do his homework. He reasons that working things out with paper and pencil is old-fashioned.
Today, parents often encourage children to use computers while doing their homework-but not Danny's mother and his teacher, Miss Arnold! When these two women put their heads together, Danny's troubles really begin.