Fourth-Grade Cooking and Physical Activity Intervention Reveals Associations With Cooking Experience and Sex

Objective: Examine the impact of Fuel for Fun: Cooking with Kids Plus Parents and Play (FFF) on children's culinary self-efficacy, attitude, fruit and vegetable (FV) preferences, physical activity (PA), and body mass index. Design: Randomized controlled trial. Setting: Eight elementary schools in 2 Northern Colorado districts. Participants: Fourth-grade students; 7-month interventions: school (S.FFF)-theory-based cook-ing + tasting lessons, active recess, lesson-driven cafeteria promotions; or school + family (S+F.FFF) with added family nights and home activities. Main Outcome Measure(s): Cooking self-efficacy and attitudes, FV preferences, PA, and measured height/weight. Analysis: Individual outcomes nested by classroom, school, and district and assessed 12 months with repeated measures controlled by sex and baseline cooking experience, with a significance level of P < 0.05. Results: The sample included 1,428 youth, 38 teachers, 4 cohorts, 50% boys, 75% White, and 15% His-panic. No intervention effect was observed. Those who cooked retained higher self-efficacy, attitude, and FV preferences (P < 0.001). Girls reported higher self-efficacy and attitude than boys. Moderate-to -vigor-ous PA and metabolic equivalent minutes increased for all students; boys retained higher levels (P < 0.001). Body mass index percentile remained stable. Conclusions and Implications: Cooking and sex were associated with all outcome measures and should be considered for intervention tailoring. Treatment impacts were not evident nesting by classroom, school, and district. Accurate assessment of school-based interventions requires rejecting student independence from group assignment assumptions.