Actively engaging adolescents in meaningful program evaluation is a topic of growing interest. One possibility for such engagement is the use of photographs as part of visual evaluation, so that youth can directly engage with the research process. In this Method Note, we describe the development and implementation of a participatory, photo-based evaluation method for youth health promotion/prevention programs. Youth in this study were participants in a gender-transformative healthy relationships program for boys. We present literature supporting the use of photographs as a visual research method and for involving youth as active participants in evaluation, and explore the feasibility, utility, and acceptability of this innovative application of existing methods based on researcher experience and youth feedback. We conclude with implications for photo-based evaluation of health promotion/prevention programs, highlighting the promise of this method for promoting critical youth engagement in evaluation and the creation of meaningful knowledge translation tools.