Educators are responsible for ensuring that students who have sustained concussions return to school with appropriate support. While school districts may provide face-to-face training through professional development initiatives, many administrators are seeking cost- and time-efficient means of training concussion teams and teachers. This study evaluated the effectiveness of an online concussion training on school professionals' awareness of, knowledge of, and confidence in concussion identification and response, as well as their ability to apply concussion knowledge. Participants watched either a 75-min Team Training video or a 30-min Teacher Training video and received access to a training handbook and supplemental resources. Results indicated that both online trainings increased confidence in concussion identification and response, as well as knowledge and awareness of concussions. Knowledge gains were similar to those found in face-to-face trainings. This provides support for the use of online concussion trainings as an effective and efficient means of professional development.