Introduction: Community nurses have a strategic role in improving clean and healthy living behaviour by providing health education to the community. Play therapy is one of the nursing interventions that can be a method of health education in school children. Objective: To determine the effect of snakes and ladders board game with peers modelling approach in improving clean and healthy living behaviour of school children. Method: The design is quasi experimental pretest post-test with control group. Calculated sample size was 126 school chidren 6-12 years old who had a problem of lack of clean and healthy living behaviour. The researchers used simulation of snakes and ladders board game in four sessions over 1 month, staging each session for 45 minutes. Data collection tool was a questionnaire consisting of variable knowledge, attitudes, and clean and healthy living behaviour skills of school-age children. Data was analysed using the paired t-test. Results: Parental education levels were low in 56% and parental incomes were low in 58%. About 75% children had a diarrhoeal disease in past 3 months. Handwashing facilities, clean water sources, and healthy latrines were readily available in 70.5%. Knowledge about clean and healthy living behaviour children increased from 44.7% to 60.9%, child's attitude about clean and healthy living behaviour increased from 43.8% to 59.5%, skills of children of clean and healthy living behaviour increased from 41.2% to 55.7% after engaging in simulationof snakes and ladders board game. Alternatively, in the control group, there was no significant change in values of knowledge, attitude, and skills variables. Conclusions: Simulation of snakes and ladders board game significantly increases knowledge, attitudes, and skills of clean and healthy living behaviour in school children. © 2020. All Rights Reserved.