Across the globe, schools are seen as an essential context for building socio-emotional capacities in adolescents, particularly for marginalized youth, who have been systematically and historically excluded from accessing opportunities and resources typically available to members of different social groups (Gil-Kashiwabara, Hogansen, Geenen, Powers, & Powers, 2007). However, despite this ideal, education has not yet reached its potential in promoting equal outcomes for all children and adolescents (American Psychological Association Presidential Task Force on Educational Disparities, 2012; Burkham & Lee, 2002; Gurria, 2016; Hampden-Thompson & Johnston, 2006). There exists a need to identify school practices that may enhance socio-emotional development and have implications for reducing disparities in academic achievement, educational attainment, and other indicators of well-being. The aim of this dissertation, therefore, is to explore school and classroom practices that may be particularly effective in supporting the socio-emotional development of marginalized adolescents. I focus on two distinct populations: youth affected by violence in Colombia, and students of color within the United States. In Study 1, I explore whether three aspects of school climate--safety, connectedness, and services--buffer the negative implications of violence exposure for adolescent development in a Colombian sample. In Study 2, I determine how culturally responsive teaching practices in schools with high concentrations of students of color in the United States can be integrated into our current conceptualization of what constitutes high quality teaching, by examining profiles of teaching practices and associations between these profiles and teacher and classroom characteristics and student behaviors.