"Evidence-based teaching practices (EBPs) foster college science, technology, engineering, and mathematics (STEM) students’ engagement and performance, yet our knowledge of what contributes to the effectiveness of these practices is less established. We propose a framework that links four social-cognitive variables—students’ trust in their instructors, growth mindset, buy-in to instructional practices, and course engagement—to long-standing desired student outcomes of academic performance and intent to persist in science. This framework was tested in classrooms identified as having a high level of EBP implementation with a multi-institutional sample of 2102 undergraduates taught by 14 faculty members. Results indicate that the buy-in framework is a valid representation of college students’ learning experiences within EBP contexts overall as well as across underrepresented student groups. In comparison to students’ level of growth mindset, students’ trust in their instructors was more than twice as predictive of buy-in to how the course was being taught, suggesting that students’ views of their instructors are more associated with thriving in a high-EBP course environment than their views of intelligence. This study contributes to the dialogue on transforming undergraduate STEM education by providing a validated student buy-in framework as a lens to understand how EBPs enhance student outcomes."