This Monograph addresses three questions: a) Can distinct trajectories of physical aggression be identified in children from 24 months to third grade? b) Do child and family characteristics and child care experiences predict membership in the trajectory groups? c) Do trajectory groups differ in their levels of academic and social functioning in third grade? Using a person-centered approach and data from the NICHD Study of Early Child Care and Youth Development, five aggression trajectories were identified: very low, low, moderate-steeply declining, moderate-stable, and high-stable. Higher...