This paper examines on-site, school-age child care and the relationship between attendance at on-site, after-school child care programs and familial, environmental, and developmental factors. Topics discussed include: (1) the quality of school-based environments in kindergarten and child care; (2) the socioeconomic status and size of families of children attending after-school child care programs; (3) the social and play behaviors of children in day care and children in home care; and (4) the degree of communication between kindergarten teachers and child care educators in on-site, after-school child care centers. The findings reported represent a small portion of a comprehensive study conducted over a 3-year period by four primary researchers in Montreal and Quebec City. Subjects were 75 children who attended school-based child care and 69 children who went home after school. There were more single parent families and fewer children per family in the day care group than the home care group. It was found that a select population used school-based child care and that the quality of school-based child care varied within and between schools. Day care history seemed to be an important factor in a child's social development. There were substantial differences between those who worked in kindergartens and those who worked in child care programs. Contains 38 references. (LB)