Although considerable research has demonstrated the importance of supportive teacher-student relationships to students' academic and nonacademic outcomes, few studies have explored these relationships in the context of high-performing high schools. Hierarchical linear modeling with a sample of 5,557 students from 14 different high-performing high schools reveals that students who believe more of their teachers care for them and students who have an adult confidant within the school fare significantly better in terms of academic anxiety, internalizing symptoms, and physical problems related to school stress than their less supported counterparts. Results also show that having support from more teachers may be a stronger protective factor for students in these schools than having a close relationship with a single adult in the school. Implications for practice and future research are discussed.