Abstract
Processes linking biological and behavioral changes in different contexts during adolescence were examined by studying an unselected cohort of New Zealand girls from childhood through adolescence when they entered either mixed-sex or all-girl secondary schools. The impact of menarcheal timing on female delinquency was moderated by the sex composition of schools; early-maturing girls in mixed-sex settings were at greatest risk for delinquency. Individual differences in delinquency were also significantly more stable among girls in mixed-sex schools than among those in all-girl schools. These contextual variations are interpreted in terms of the differential distribution of reinforcements and opportunities for delinquency.