The Early Symbolization and the Transition to Literacy Project (1976-1989) was a group of closely related studies, all of which centered on the study of representation capacities in younger children. The original longitudinal study followed closely the development of young children, specifically the maturation of symbolic capacities in each of several areas, and built a model for early symbolic development. A second study addressed different patterns of symbolic development and focused on the onset and growth of symbol use in fifty school-age children.