Twenty congenitally blind infants were placed in a panelled framework with various tactile and auditory objects for 20-minute periods. Results indicated that subjects improved their performance of spatially related activities when exposed to an environment helping them understand the concept and permanence of objects and the production of…

Describes an attempt to study and map the development of children's conceptions of materials. Interviews with preschool, first-grade, fourth-grade, and seventh-grade students revealed a dramatic improvement during the years studied in children's abilities to talk and think about materials. (ML)