Short-term outcomes associated with participation in REbeL, a peer-led dissonance-based eating disorder prevention program for high school students, were evaluated. Seventy-one students across the three high schools were enrolled in the study (REbeL N = 48; Control N = 23) and were assessed on measures of eating attitudes and behaviors, body image, weight bias, self-esteem, empowerment, and mood at the beginning of the school year; 37 REbeL students and 20 control students completed assessments at the end of the school year. Mixed effects GLM compared groups on outcomes at the end of the academic year. When controlling for baseline scores, students in both REbeL schools, compared to control school students, demonstrated statistically significantly lower scores at post-test on the EDE-Q Global score, the EDE-Q Restraint, Eating Concern, Shape Concern and Weight Concern subscales, and the Body Checking Questionnaire (all ps < .05). This study provides preliminary empirical support for the REbeL program.