Addressing the global public health concern of reducing suicidal behavior in young populations requires a comprehensive approach. This problem represents a significant challenge for LMICs, which are in a constant struggle to increase their mental capital through rapid implementation of interventions that are effective in reducing MH problems at a population level while also making the best use of limited resources. This study combines insights from two methodologies: a participatory approach in system dynamics modeling and simulation, and a workshop-based exploration of mental health outcomes and interventions. The system dynamics model, developed through three workshops with 78 stakeholders, projects 6,670 suicide attempts and 347 suicides among 7?17-year-olds from 2023 to 2031 under a business-as-usual scenario. Mental health issues in 12-17-year-olds are projected to increase from 18·9% (2023) to 27·8% (2031). Notably, school-based suicide prevention and gatekeeper training emerge as the most effective strategies, reducing suicide attempts and suicides by over 20%. However, the study highlights challenges, such as the impact of discontinuous funding on hindering effective suicide prevention efforts. Integrating system dynamics and participatory approaches provides a robust framework for decision-makers, offering insights into strategic resource allocation and interventions that can be tailored to specific contexts for maximum impact on youth mental health.