Top researchers examine the cognitive significance of the growth in children's ability to express themselves symbolically, whether that involves communicating linguistically, mathematically, logically, or through some other symbol system expressed in speech, gesture, notations, or some other means. The book contributes to refining and answering questions regarding the nature, origin, and development of symbolic communication in all its forms, and their consequences for the cognitive development of the younger child at home and the older child at school.