Abstract
The critical need everywhere in the 21 century world is to prepare students to lead healthy and fulfilling lives by providing them with relevant educational programmes inclusive of co-curricular practices. The study evaluated influence of co-curricular practices on effectiveness of substance abuse preventive intervention among secondary school students in Kakamega County. It adopted a cross-sectional survey design. The target population was 59675 form three students, 1080 class teachers, 530 G/Cteachers and 12 sub-county directors in the study area. Simple random and purposive sampling techniques were used to select the sample size; 381 students, 108 class teachers, 53 G/C and 12 sub-county directors of education. Structured questionnaires, focus group discussion guide and interview guide were used to collect data which was subjected to descriptive and inferential analysis using Statistical Package for Social Sciences. Based on the correlation results, the study established that there is a positive association between co-curricular practices and effectiveness of substance abuse preventive interventions in the study area. From the regression results, co-curricular practices is a significant predictor. Therefore at 95% confidence limit co-curricular practices have statistically significant influence on effectiveness of substance abuse preventive intervention. The practices range from competitive games and sports, with the highest influence, followed by time allocated, frequency of participation, down to stars in co-curricular and lastly clubs. Overall, the study concludes that the success of effectiveness of substance abuse prevention is dependent on co-curricular practices. The intervention range from school administration, school location, open communication and finally random checks