<p>This study presents a holistic decision analysis framework for optimizing school garden interventions in public and private schools across Vietnam. We evaluate the effects of such interventions on child health, biodiversity, and economic outcomes, analyzing five investment scenarios, from passive gardens to STEM-focused programs. Using food environment and food system frameworks, we mapped impact pathways to identify trade-offs, synergies, risks, and uncertainties. Monte Carlo simulations, sensitivity analysis, Pareto optimization, and Expected Value of Perfect Information (EVPI) guided the evaluation of decision options and key success factors. Results indicate that passive gardens consistently provide greater biodiversity and health benefits, while STEM gardens face financial and operational barriers, particularly in public schools. Key drivers of success include garden-related school events, teacher training, and community support. Findings underscore the financial constraints in public schools compared to private institutions, revealing critical trade-offs among economic, biodiversity, and health outcomes, and highlighting the need for targeted investments to mitigate these uncertainties.</p>