The current research used longitudinal data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development (N=1103) to examine the developmental cascades of prosocial behavior, academic competence, and peer exclusion from 3rd grade to 6th grade, and how they are linked with adolescent depression at 15 years old. The results in the current research showed that 3rd grade prosocial behavior decreased 4th grade peer exclusion and increased 4th grade academic competence; 4th grade peer exclusion, in turn, negatively influenced 5th grade prosocial behavior, and 4th grade academic competence positively influenced 5th grade prosocial behavior; then, 5th grade prosocial behavior decreased 6th grade peer exclusion; finally, 6th grade peer exclusion increased depression at 15 years old. Implications for developmental cascade models, progressions, and preventive interventions were discussed.