Noting that it is by studying children's regular activities and their roles and interpersonal relationships that we come to understand how children develop as members of their cultural groups, this study examined children growing up in urban settings in a variety of societies. The study used an ecological perspective largely based on Bronfenbrenner's framework. Participating in the study were 130 children, ages 28 to 45 months at Time 1, and their parents living in medium sized cities; this paper focuses on findings from 62 children from the United States, Russia, and Estonia. Data were collected by means of parent interviews and questionnaires, and from observations of children for 20 hours over the course of a week. Activities of interest included lessons, work, play, exploration, entertainment, and conversation. Findings indicated that middle-class parents in all three countries were more likely to value self-direction for their children and were more interested in freedom for their children than were working-class parents, who were more interested in controlling and disciplining their children. There was considerable similarity across cultures in the activities in which children were engaged. Children all spent the majority of their time in play, with lessons, work, and conversation occupying much less time. Children in middle-class U.S. and Estonian homes were more likely than their working-class counterparts to be involved in activities possibly related to subsequent academic competence, such as academic or skill/nature lessons, play with academic objects, and conversation with adults. In Estonia and Russia, middle-class children were viewed by their teachers and parents as more competent academically than were children from working-class families. There were also cultural and social class variations in the relationship of preschool children's activities to teacher perceptions of competence at the end of their first year in school. (Contains 14 references.) (KB)