<p>Schools are a critical vehicle for promoting child well-being. Through their climate, organization, policies, and practices, school structures promote or inhibit the developmental trajectories of their students. Schools are increasingly seeing a need for students to develop social emotional skills, particularly in the domain of emotion regulation (ER). This study investigates the influence of school climate, school contexts, and individual demographic factors on the development of ER skills among youth in nine countries. Utilizing data from the Organization for Economic Cooperation and Development’s Survey on Social and Emotional Skills, this study examines how school contexts (e.g., school climate and school demographics) and individual factors (e.g., sex, SES, and immigrant background) impact students’ abilities to regulate their emotions. The results from hierarchical linear models revealed that students’ perceptions of their school’s climate (belonging, relationships with teachers, and school anxiety) significantly enhance their ER skills, while students’ perceptions of negative school climates were associated with worse ER outcomes. School-level demographics (proportion of minoritized students) predicted ER skills in individual students while individual demographic factors did not have an association with ER skills, with the exception of age. This study underscores the importance of equitable, supportive school environments in fostering youth ER. Policies that reduce inequities, particularly in schools serving minoritized students, are critical for enhancing the emotional and behavioral competencies essential for long-term success and well-being.</p>