IRCT2015061722790N1 IRCT 2015-08-12 Vice Chancellor for research of Iran University of Medical Sciences Investigating effect of a physical activity education based on planned behavior theory on physical activity among 7-12 years old girls with obesity - Investigating effect of a physical activity education based on planned behavior theory on physical activity among 7-12 years old girls with obesity 2015-09-25 anticipated 100 Complete https://irct.ir/trial/19581 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Other design features: random number generation using calculator. N/A Obesity and Overweight. Intervention 1: intervention group, five session education based on planned behavioral theory with PowerPoint and videos,time of each session is 45 minutes, sessions are designed based on the theory and have been approved by 10 professors. Intervention 2: control group, in this group no intervention will be occur.