We introduced “Computer Science Unplugged” to our classes in junior and senior high schools. “Unplugged” is an education method of computer science without students using a computer at all. For our classes, we developed original teaching materials and methods for Unplugged. As a result, the students could learn the topics of computer science with interest by using Unplugged. They enjoyed the games in Unplugged and thought about the topics deeply at the same time. We confirmed that students enhanced their motivations, thinking abilities, and imaginations.