Oral health education is an important part of oral health promotion and an essential and basic part of oral health services. This double blind interventional study evaluated the effect of oral health education on oral hygiene knowledge, practices, plaque control and gingival health among 13-15 years old school children in Bangalore city. Oral hygiene knowledge and practices were assessed by a questionnaire and clinical examinations (Turesky-Gilmore-Glickman modification of Quigley Hein plaque index; Loe and Silness gingival index) were performed at baseline, 3, 6 and 9 months. Oral health education was provided for the Experimental I (n=150)using power-point presentation and Experimental II group (n=150)using power-point presentation & toothbrushing demonstration with reinforcement at 3 & 6 months. The control group (n=300) did not receive any intervention. The study concluded that although a lecture method can improve the knowledge and practices, individual toothbrushing demonstration and active involvement of school children with reinforcement every 3 months can yield better results. This will help a long way in decreasing plaque levels and subsequently improving gingival health.