The longitudinal effect of perceived social support on school engagement: A multiple mediation model examining the role of emotion regulation and left-behind status.

School engagement generally declines during adolescence and was reported to be worse in Chinese adolescents in rural areas compared to those in urban cities. Extensive studies have investigated the roles of perceived social support (i.e., students' perceived teacher support, family cohesion, and peer support) in shaping students' school engagement. However, inconsistent findings were documented. Furthermore, the underlying mechanism between perceived social support and school engagement lacks investigation. Therefore, informed by the bioecological model and the process model of interpersonal strategies, this longitudinal study examined (a) whether three sources of perceived social support (i.e., teacher support, family cohesion, and peer support) at Time 1 were associated with school engagement at Time 2 both directly and indirectly through emotion regulation (i.e., cognitive reappraisal and expressive suppression) at Time 2 and (b) whether such pathways differentiated between non-left-behind adolescents and left-behind adolescents (LBA), with left behind being a unique cultural phenomenon in rural China. Structural equation modeling was employed to test the multiple mediation models among 3,043 Chinese rural adolescents (46.86% boys; M_age = 15.82 years, SD = 1.56) in two rural boarding schools in Guizhou and Gansu province. In the overall sample, (a) cognitive reappraisal fully mediated the association between teacher support and school engagement. (b) Family cohesion was positively associated with school engagement, while the indirect effects were not significant. Different pathways were revealed in non-left-behind adolescents and left-behind adolescents. (c) Peer support had no direct or indirect effect on school engagement. This study contributes to the understanding of how social-emotional processes influence school engagement and informs culturally responsive strategies and practices that enhance school engagement. (PsycInfo Database Record (c) 2025 APA, all rights reserved).