Non-suicidal self-injury--the deliberate destruction of body tissue without suicidal intent--has become relatively common among U.S. adolescents: 18 percent of school-based youth report self-injuring at least once. The authors give suggestions and vetted resources for how schools can safely address the issue of self-injury, in ways that let students know they can find support--and how individual educators can sensitively talk with a student struggling with a habit of self-harming.