A reactor is an example of an immersive interactive play in which animated images are projected onto the floor. A reactor allows people to walk on images and interact with them using their feet. With reactors, people can stomp on kernels of popcorn, shoot a pool using their big toes, or wade through a shallow surf on pristine beaches. This interaction between people and pictures is made possible by infrared cameras that send a rapid sequence of images to a computer, where software builds a constantly updated model of who's in the field, where they are, and what they're doing. In this article, the author discusses the possible applications of reactors to education in the future.