A sample of 398 children was followed up from ages 5 to 12 to investigate the relation between peer group rejection and classroom participation. The participation trajectories of individuals and groups of children who were rejected for differing periods of time were examined both during and after rejection using piecewise growth curve analyses. The results showed that whereas during periods of rejection, children exhibited negative or negligible growth in participation, when nonrejected, they manifested positive growth. These findings corroborated the hypothesis that (a) peer rejection creates constraints that inhibit children's classroom participation and (b) the cessation of rejection enables children to become more active and cooperative participants in classroom activities.