Background: Youth who have experienced trauma or other adverse childhood events have the potential to uniquely benefit from physical activity (PA). However, how PA is administered in schools can be re-traumatizing and fail to create positive experiences through movement. We sought to develop role-specific training to help increase the implementation of trauma-informed PA. Methods: Guided by intervention mapping methodology, we developed "Move & Thrive"--a brief web-based training about trauma-informed PA. We then conducted a pilot evaluation of this training using a pre-posttest design with no control group in a sample of youth sport coaches, parents of school-aged children, and teachers (n = 150) recruited from an online opt-in non-probability panel. Results: Mixed methods feedback found that "Move & Thrive" was highly acceptable. Across all roles (coaches, teachers, and parents/guardians) there were statistically significant increases in all targeted implementation determinants (knowledge, attitudes, self-efficacy, and perceived resources/support), with moderate to large effect sizes. Conclusions: These results provide the foundation for a larger, adequately powered trial with randomization and follow-up to assess the implementation of trauma-informed PA.