IRCT2013012412255N1 IRCT 2013-08-06 Tehran University of Medical Sciences prevention and control of obesity in primary school children in Tehran Developing and evaluating of an interventional model to prevent and control childhood obesity in the fifth-graders. Tehran 2012-11-06 anticipated 360 Complete https://irct.ir/trial/12351 interventional Randomization: Randomized, Blinding: Not blinded, Placebo: Not used, Assignment: Parallel, Purpose: Prevention. N/A overweight/obesity. Intervention 1: The approach of intervention is knowledge translation. The intervention will be multi-component including nutrition education (parents and students), increased physical activity, and changing of the schools, environment. The education will be monthly and weekly sessions for parents and students, respectively. The parents are taught about childhood obesity and its causes. They will also learn strategies to increase physical activity and vegetable and fruit consumption, as well as decrease consumption of high energy foods by their children.Nutrition education of the students will be done done by health instructors of the schools who have been trained for this work. The content of the education will be mainly Iranian food pyramid, food groups, and energy value of the food groups. To increase physical activity of the students, weekly exercise sessions under supervision of their schools’ coach will be done in schools. Finally, the school canteens will becolsely supevised with particular attention to the type of foods (snacks, etc.) offered for sale. Intervention 2: During the intervention period nothing will be done in comparison schools. At the end of intervention an educational session for parents(1.5 h) will be held for all comparison schools.