Introduction: Overweight and obesity represent a serious and growing public health problem in children. Objective: To determine the effectiveness of educational interventions in Latin America for the prevention of overweight and obesity in school children aged 6 to 17. Methodology: The MEDLINE, LILACS and EMBASE databases were consulted between February and May 2014 to identify randomized controlled studies and longitudinal studies that evaluated the effects of educational interventions aimed at preventing overweight and obesity in Latin American children. The risk of bias and methodological quality was assessed using the PEDro scale and the CASPe instrument. Results: Twenty-one studies were included (n=12,092). Different types of interventions were identified, such as nutritional strategies, promotion of physical activity practice and changes in the environment. The mixed interventions, which combined nutritional changes with the promotion of physical activity, were the most effective, as their results showed positive changes in the variables associated with overweight and childhood obesity. No evidence of publication bias was observed. Conclusion: School-based interventions that combine adequate nutrition and the promotion of physical activity are effective in the prevention of childhood overweight and obesity in Latin American schoolchildren, although interventions in the family environment should be incorporated to allow for an integrated approach, associated with greater responses to behavioural change in schoolchildren.