OBJECTIVE: To evaluate a secondary school smoking prevention program in a small rural Norwegian municipality. DESIGN: The project applied grade specific intervention strategies to all students grades 6-9 and comprised a total of 32 lessons over a period of 3 years, with high student activity. A non-randomised control group was constituted by all 6th-9th grade students in municipalities of similar characteristics in the same county. Results were recorded in annual class-based surveys. SUBJECTS: The intervention group totalled 187 and the control group 364 students. MAIN OUTCOME MEASURES: Prevalence of daily and occasional smoking and number of cigarettes smoked, during the intervention period. RESULTS: An 80% lower rate of daily smoking and 50% fewer cigarettes smoked by daily smokers. Lower rates of smoking in 9th grade occurred mostly among girls. CONCLUSION: The project resulted in a lower recruitment of daily smokers up to grade 9, as well as fewer cigarettes smoked by daily smokers. The intervention was more successful among girls than boys.