Abstract
Socioeconomic inequality remains a persistent determinant of adolescents’ academic outcomes, yet less is known about the interplay between the psychological and relational mechanisms through which these disparities influence school engagement and success. This study examines how socioeconomic status (SES) shapes academic achievement through its effects on teacher support, mental health, and school motivation. Using data from 1,107 9th-grade students in the National Longitudinal Study of Adolescent to Adult Health (Add Health), structural equation modeling (SEM) was conducted to test a pathway model in which school motivation serves as a central mediator. Results indicated that higher SES was associated with better mental health, but unexpectedly lower perceived teacher support. Both teacher support and mental health significantly predicted higher school motivation, with teacher support emerging as the strongest predictor. Unexpectedly, school motivation negatively predicted academic achievement, suggesting potential suppression effects or the influence of unmeasured factors such as stress or perceived competence. Mediation analyses further revealed that teacher support, but not mental health, significantly mediated the relationship between SES and motivation. These findings highlight the critical role of teacher-student relationships and reinforces the complex pathways through which socioeconomic disparities can shape academic outcomes.