Maintaining good oral hygiene is very important, especially in children, as it can prevent dental caries that may also affect permanent dentition. When proper oral hygiene is not maintained, children may suffer from pain and recurrent caries, and in rural areas, extraction is often the only treatment performed. Answers to questions concerning the effectiveness of health education tell us whether or not it is worth doing and, if so, what works best under what circumstances. Data from well-designed evaluation studies also play a role in further developing such interventions.A cross-sectional study was implemented in Chennai, Tamil Nadu, involving 640 samples aged 13-16 years. Three schools were selected from Porur block, based on accessibility by vehicles throughout the year, and all five schools in the block had given permission for the workshop. The sample size was calculated from previous study articles, and three schools were selected by random sampling method/lottery method. The study was conducted on 640 primary school children, 320 girls and 320 boys. A self-administered questionnaire was distributed among the class teachers to distribute to the children, and they were also educated with a workshop conducted thrice in a period of two months. The same questionnaires were given to them after the oral health education program to assess improvement.The objective of the study was to predict the effectiveness of health education in preventing dental caries in children using a self-administered questionnaire.