Purpose: The purpose of this study was to evaluate a weight-related teasing prevention program implemented for both female and male students in a school setting. Methods: Junior High School students (N = 143) in seventh grade were invited to participate in the program. One hundred eighteen participants completed pre- and posttest surveys to assess bullying frequency and to evaluate an efficacy of the 8-week prevention program. Results: Data at posttest revealed the number of students who reported being bullied decreased by 7% (n = 8). The incidence rate of self-reported bullies was reduced from 18% to 14%. The levels of body esteem and self-esteem were statistically higher among the participants at posttest. Male participants showed a significant improvement on the Ideal-Body Stereotype Scale-Revised compared to female participants. On the other hand, the difference in mean scores on victimization of weight-related and competency teasing between pretest and posttest was statistically higher among female participants. Conclusion: The intervention program helped the participants increase body esteem and self-esteem levels. Although female participants tended to report more victimizations from previous teasing (weight and competency) incidents at posttest period, levels of stereotyped images towards women among male participants were statistically reduced after the intervention program. Recommendations: Body image or weight-related issues are rarely discussed enough for male students in a school setting. One reason is lack of resources for health teachers to address the particular issues for both female and male students. Simply, many teachers may feel uncomfortable or less confident to discuss the particular issues. Therefore, more research and resources for teachers are necessary to reduce weight-related teasing and other issues in a school setting.