The effectiveness of a web-based prevention program designed for elementary school teachers was examined in 78 elementary school teachers and 89 local public health practitioners (who provide support to schools). Participants were assigned to either the intervention (n = 95) or comparison (n = 72) study groups. All participants completed self-report online measures prior to, and following, the 60-day study period assessing knowledge about various factors that influence body image in children and efficacy to fight weight bias in the school. Information was also solicited on the feasibility of, and on the perceived benefit of the web-based program as a knowledge translation tool, in terms of layout and content. The Student Body program was found to be successful in improving knowledge concerning facts about dieting among the teacher participants, and in increasing efficacy to fight weight bias among the public health participants. Overall, the feedback was very positive concerning the layout and content of the Student Body. Participants reported an overall improvement in their awareness about how weight bias can be present in their teaching practices, and how this can trigger body image concerns among their students. Findings have implications for using the web to engage teachers in the prevention of disordered eating among school age children.