Stepping Up! offers inspiring suggestions for ways teachers and teacher educators can stand up and speak out for students to create welcoming classroom climates for LGBTQ and gender diverse youth. Building from ten years of collaborative longitudinal inquiry, including interviews with parents, students, teachers, and administrators, the authors share stories from different perspectives to support teachers with concrete examples of advocacy. The authors show teachers how to 'step up' by working with students, through and beyond curriculum, and by working with families and administrators to improve school culture for LGBTQ and gender diverse students. Additionally, they explore the potential constraints involved in such social justice work, and share strategies and resources for transforming schools to be more queer-friendly.