Because bullying behaviors occur across the many spaces that exist within schools (e.g., classrooms, gyms, bathrooms, playgrounds, cafeterias), and because students often move between classrooms and teachers, it is critical for schools to take a schoolwide approach to preventing bullying and harassment (Jones & Bouffard, 2012; Bradshaw, 2015). School-level strategies refer to actions that administrators and other school leaders can take to nurture a positive school climate and to prevent bullying and harassment. Therefore, school-based bullying prevention programming must begin with universal efforts, involving all administrators, teachers, counselors and other educational support providers (e.g., bus drivers, cafeteria employees, janitors, office staff). This toolkit provides guidance for school level strategies in the following areas: (1) Guidelines for Building Safer School Climates; (2) Structural Shifts & Restorative Practices that Promote a Positive School Climate; (3) Positive School Culture-Building Strategies; (4) Developing or Updating Anti-Bullying and Anti-Harassment Policies; (5) Addressing Cyberbullying; (6) Intervention Strategies; (7) Dealing with Teachers Who Bully Students; and (8) Informing and Collaborating with Families.