Development and evaluation of a multi-media training program for elementary school bullying and abuse prevention: radKIDS 2.0 - ABSTRACT Child abuse, peer violence, and injury continue to be major public health challenges, jeopardizing the healthy development of millions of American children every day. Post-pandemic, elementary schools are reporting significant delays in children’s social development, as well as higher rates of harmful internal and externalizing behaviors. Child bullying by peers is linked to psychosis by late childhood and adolescence, harming school outcomes due to higher absenteeism, reduced classroom attentiveness, increased school drop-out, and greater risk for teen substance abuse, delinquency, and violent behavior. Demand for effective prevention of bullying, sexual abuse, child abduction/trafficking, and abuse have grown over the past two decades, with many states mandating school-based programs to help reverse violent and other adverse behaviors among children in schools. Currently, only 25% of school-based prevention programs have been shown to be somewhat effective in reducing peer violence. Also, most successful bullying prevention programs do not align with nationally recommended safety guidelines deemed essential for effectively protecting children from abuse, bullying and other forms of violence. The radKIDS® Personal Empowerment and Safety Education Program is a school-based program developed in response to these national recommendations. radKIDS® uses activity-based skill training to help elementary aged children develop personal safety boundaries, critical thinking skills for responding to threats of danger, age-appropriate coping strategies for dealing with current and past victimization, self-assertiveness and physical skills for self-defense, communication skills for reporting incidences to parents/adults, and increasing child self-worth—the program’s cornerstone for personal safety and healthy development for elementary students. Within Phase I, we showed that online training, with enhanced student curriculum, met all benchmarks in instructor self-efficacy, knowledge gains, and program usability, acceptability, user satisfaction, consumer satisfaction, and fidelity of implementation. Within Phase II, our goals are to: 1) Complete full adaptation of radKIDS® instructor training and student instruction into a blended online/in-person instructor training and instructional delivery system that can be used for broad-scale dissemination among low income and rural elementary schools, and 2) Conduct a clustered randomized trial with 40 elementary school, with one 4th grade classrooms per school, in the states of California, Oregon, and Florida. We will assess a) student growth in knowledge, safety skill self-efficacy, confidence in help-seeking and in maintaining personal safety, and child self-esteem, and b) levels of instructor knowledge of student personal safety domains, usability of program, acceptability of program, consumer satisfaction, and fidelity of implementation. Exit interviews will be conducted with school administrators to assess program satisfaction and strategies for adoption and full implementation in schools. If the modified program is effective and practical for use in schools, wide-spread implementation as a result of effective marketing could have a large impact on public health by decreasing incidents and risks of harm and reducing child trauma due to preventable violence, abuse, and injury.