Student and school characteristics modify the impact of SNAP-Ed on student dietary and physical activity outcomes.

Objective: To examine the impacts of school-based CalFresh Healthy Living (CFHL-California's SNAP-Ed) interventions post-COVID-19-related school closures and whether student and school characteristics modified intervention impacts on student diet and physical activity (PA).

Design: Quasi-experimental, two-group, pre-post, self-report.

Setting: CFHL-eligible public schools ( = 51; = 18).

Participants: 4th/5th grade students ( = 2115; = 1102).

Results: CFHL interventions were associated with an increase in consumption frequency of fruit (0·19 times/d ( = 0·015)) and vegetables (0·35 times/d ( = 0·006)). Differences in baseline diet and PA behaviours were observed by student race and gender and by whether the proportion of free and reduced-price meal (FRPM)-eligible students was above the state average. Notably, students in schools with FRPM above the state average reported more frequent consumption of sugar-sweetened beverages (Mean (se): 3·18 (0·10) . 2·58 (0·11); = 0·001) and fewer days/week with 60+ min of moderate-to-vigorous PA (MVPA) (Mean (se): 2·8 (0·10) . 3·21 (0·12); = 0·020) than those at schools with FRPM at/below the state average. Student gender, school urbanicity and school FRPM modified the relationship between the interventions and certain dietary and/or PA outcomes. Interventions were associated with greater increases in vegetable consumption in more urban schools ( (95 % CI) = 0·67 (0·15, 1·20)), and greater increases in fruit consumption ( (95 % CI) = 0·37 (0·07, 0·66)) and in MVPA in higher FRPM schools ( (95 % CI) = 0·86 (0·33, 1·39)).

Conclusions: Findings reaffirmed effectiveness of school-based CFHL interventions. We identified existing student and school-level disparities and then observed that interventions were associated with greater increases in MVPA in the highest FRPM schools. Findings can inform an equity-centred approach to delivery of school-based interventions that facilitate equal opportunity for all children to achieve lifelong health.