Adolescents experience challenges navigating psychological, physiological, and emotional transformations. This article contributes to research into how middle school and high school environments can reinforce the needs of students through the transition from middle school to high school. In this grounded theory study, we interviewed 11 experienced, successful middle school principals in high-performing schools to explore practices and behaviors in supporting this transition. Participants noted the importance of maintaining high expectations while providing students with continuous nurturing, support, and opportunities to develop into responsible and self-sufficient young adults. These principals built positive school environments by promoting a shared vision based on regular collaboration among all stakeholder groups. Principals affirmed the middle school concept practice of exposing students to (a) rigorous, engaging, academic classes; (b) a variety of career exploration and elective course offerings; and (c) opportunities to teach positive character, soft skills, and self-advocacy. Findings reaffirmed the benefits of student-centered schools with effective administrators and teachers who seek continuous improvement, practice professional collaboration, implement student-centered programs/interventions, and make decisions based on the best interest of the students. The article concludes with implications for practice and further research.