Very young children learn by exploring their surroundings, mostly by playing, during which they construct mental representations of the world. In fact, prior to Piaget's formal operational stage, children need concrete, hands-on experiences rather than abstract concepts to support more natural learning, developing, and thinking. In terms of technology, this observation means that before grade four there needs to be a direct link between the real world and digital data. However, traditional computer interactions fall short of supporting these principles and do not provide the type of direct contact most familiar to preschool children. In this article, the authors describe a prototype system which they developed to deliver computer-based instruction to young children through tangible manipulatives. (Contains 3 figures.)