Background: School-based physical activity (PA) programs are an equitable, evidence-based approach to combat health and PA disparities. This study examined factors associated with implementation of BE Physically Active 2Day (BEPA 2.0), a K-5 school-based PA program, and examined how support from Cooperative Extension via Supplemental Nutrition Assistance Program Education (SNAP-Ed) partners influenced implementation. Methods: Teachers in schools receiving BEPA 2.0 trainings were surveyed about program use 3-6 months post-training. Descriptive and chi-square analyses were conducted to evaluate the relationships between implementation factors (e.g., training, support, barriers) and program delivery. Logistic regression was used to summarize the odds of program delivery related to implementation factors. Findings: Responses were returned by 355 teachers. The odds of program delivery among trained respondents were 2.64 (1.22, 5.47) times the odds among untrained respondents. Most implementors (72.4%) provided activities 1-2 times/week. More frequent implementation (= 3 times/week) [OR = 2.43 (1.27, 4.73)] and fewer barriers were reported among those who received support from SNAP-Ed partners (p = 0.01). Implications for School Health Policy, Practice, and Equity: SNAP-Ed program partnerships should be considered when implementing school-based strategies to increase PA opportunities for vulnerable youth. Conclusions: High PA program implementation among trained teachers was enhanced with partner support.