Longitudinal study of the influence of puberty on school engagement and widening achievement gaps in secondary education

A female advantage in education is evident during secondary education, and fewer boys continue into tertiary education. Current educational theories fail to explain the changes observed in STEM subjects. The earlier onset of puberty in girls has been linked to the female advantage. Puberty is associated with a wide range of developmental changes in adolescence. However, the mechanisms connecting these developmental processes to academic achievement remain underexplored. Using the longitudinal panel and educational achievement data of 5,795 UK school students, this thesis investigates the developmental and psychosocial mechanisms underlying educational outcomes during adolescence. Study 1 explores how sex differences in academic achievement evolve from childhood to age 16 across core subjects, revealing a widening female advantage, particularly in language and increasingly in STEM disciplines. The findings challenge the assumption that men are more prevalent at higher levels of STEM achievement. Study 1 also examines the role of teacher grading bias, finding limited evidence that it substantially contributes to sex achievement gaps. Study 2 extends the analysis by examining the association between puberty, academic self-concepts, educational expectations and school engagement. While puberty was associated with declines in school engagement, especially among girls, self-concepts and expectations emerged as stronger predictors of engagement. This thesis highlights that adolescent identity development can be influenced by peers, parents, and teachers, thereby shaping educational trajectories. Additionally, structural and societal factors may drive girls to prioritise their education to achieve a living standard comparable to that of boys. The higher prevalence of special educational needs (SEN) diagnoses among boys likely contributes to sex achievement gaps. This thesis recommends future research to disaggregate school engagement findings by sex and SEN diagnosis to better understand subgroup risks. Further research is needed to clarify the relationship between adolescent development and academic achievement and the longitudinal impact of teacher stereotype endorsement.