Sex differences in academic achievement in US adolescents: the role of maturation and impulse control

This study investigates mechanisms underlying girls’ academic advantage over boys by examining the role of physical and pubertal maturation. Using longitudinal data from the Add Health study, we analyzed whether sex differences in maturation explain girls’ higher grade 10 GPAs, and whether these associations are mediated by planfulness or impulse control. Path analysis revealed that females’ higher GPAs were partially explained by their advanced physical maturation as rated by the interviewer (explaining 2.4 percent) and greater impulse control (explaining 7.7 percent), controlling for cognitive ability and other potential confounders. Still, a significant direct effect of biological sex on GPA remained, suggesting additional unexplained mechanisms. Planfulness predicted GPA but did not vary by sex, and neither planfulness nor impulse control were associated with perceived relative maturation.