Childhood obesity, a serious public health concern, has a high prevalence with long-term negative physical and mental health consequences. Prevention and treatment of obesity are considered a priority among pediatric health care providers. This participatory action research, using empowerment strategies with 110 school stakeholders, aimed to develop a family and school collaborative program for promoting healthy eating and physical activity for school-age children. Quantitative data were analyzed using descriptive statistics, while qualitative data were subjected to content analysis. The study findings revealed the program had five core components including: situational analysis, family and school collaboration, exploration of effective interventions, implementation of planned activities, and monitoring and evaluation. Methods of program implementation included: group discussions; brainstorming and mind mapping; group meetings; and, participatory workshops. The impact of program implementation was evident, with family and school collaboration, in: initiating school policy, developing practical guidelines and implementing obesity prevention activities. Activities created a supportive environment by disallowing sale of sodas and unhealthy snacks; developing a curriculum for enhancing the capacity of student leaders; promoting physical activity; providing a healthy school lunch and snack menu; providing obesity prevention education; conducting child nutrition status surveillance; and, developing a database for tracking children’s status over time. The program could be used as a guideline for nurses and health care personnel to enhance partnerships, between families and schools, in order to promote healthy eating and physical activity in school-age children.