Research focused on undergraduate science, technology, math, engineering and math (STEM) student success has demonstrated the positive contribution of active learning strategies. Using a sociopolitical lens, which recognizes that students arrive with varied social identities and historical legacies, this study examines the role that faculty play in preparing students for active learning interactions. Four cases of STEM classrooms are presented, drawn from interviews with faculty and students, with a focus on students of color and first-generation college students. Faculty set expectations for student engagement in active learning and established intentional, effective routines; even skeptical students appreciated the efforts to support learning. However, faculty had not prepared for identity-related tensions. Students conveyed experiences of peer disinterest, peer exclusion, and alienation while emphasizing an intersectional perspective on social identity across race, socioeconomic background, disability status, and queer community membership. Implications for future research and practice are discussed.