This study adds to the growing literature linking children's experiences in the environment to individual differences in their developing skills in attention, memory, and planning. The authors asked about the extent to which stimulating and sensitive care in the family and in the child-care or school environments would predict these cognitive outcomes. The authors also questioned the primacy of experiences in the first 3 years of life. Data from a sample of 700 first graders whose experiences in the home and in child care or school were evaluated since early infancy revealed that the cumulative quality of the child-rearing environment was related to attention and memory but not to planning and that the quality of the family environment was more strongly associated with outcomes than was the quality of child care and of school. The quality of both children's early (6 through 36 months) and later (54 months and first grade) environments predicted performance on the attention and memory tasks.