Effects of early child care on children’s functioning from 4½ years through the end of third grade (M age = 9.0 years) were examined in the NICHD (National Institute of Child Health and Human Development) Study of Early Child Care. Some effects of early child care that had been detected prior to school entry were maintained through the end of third grade. Higher quality child care continued to be linked with higher scores on standardized tests of math and reading achievement and of memory through third grade. More time periods of center care were associated with better memory, but also with more conflictual relationships with teachers and mothers. Some new effects were detected: More hours of child care were associated with poorer work habits and poorer social skills through third grade. Other effects, such as relations between amount of care and externalizing behaviors and teacher-child conflict, decreased during the primary grades and were not significant in Grade 3. These findings support the relative independence of quality, quantity, and type of child care in relation to child developmental outcomes.