After mass crises, trauma-exposed children report increased psychological distress, yet most receive no mental health (MH) services and supports. This study identifies factors associated with teachers' reports of outreach to school-based MH providers (such as social workers, psychologists, and counselors) as well as provision of informal supports after the 2013 Boston Marathon bombing and suspect manhunt. Boston-area K-12 teachers in 72 schools (N = 147) were surveyed two to five months after the attack. Teachers reported their perceptions of students' attack exposure, observations of classroom-wide psychological distress, availability of school counseling resources, outreach to school-based MH providers (for example, consultation and referral), and provision of informal supports (for example, talking to students one-on-one). Results indicated that teachers' report of outreach to MH providers was associated with increased observations of classroom-wide psychological distress and heightened perceptions of student trauma exposure. In contrast, provision of informal supports to students was not associated with either perceived exposure or distress. Furthermore, teacher knowledge of increased school-wide counseling resources was not associated with teacher-reported outreach to MH providers. Referral trends among teachers following mass crises can provide important information to school social workers who seek to identify students in need of MH services.