PROJECT SUMMARY Schools face rising mental health needs among children that have been exacerbated by social isolation, increased economic stress, and reduced societal supervision during the COVID-19 pandemic. U.S. public schools are the most common institutional entry point to mental health services for children, and school-based health centers (SBHCs) increasingly serve as a “medical home” for vulnerable children. Yet there are significant gaps in our understanding of SBHCs’ effectiveness and the extent to which they are reaching underserved subgroups of children. Research on SBHCs has largely neglected the study of children’s mental health outcomes; few studies have sought to study in-depth the mechanisms by which SBHC have the potential to improve children’s outcomes; and we lack longitudinal research on SBHC effectiveness. We will fill these critical gaps in research and generate new, generalizable knowledge on program and policy levers that SBHCs can deploy to increase their effectiveness and reduce inequities in children’s health and education outcomes. A key innovation of our proposed research is our use of a high-quality, linked health and education dataset that encompasses the population of children in Tennessee who have a Medicaid record at any point in time between 2006 and 2019, with the plan to add data through 2025. Our longitudinal data begin well before the Affordable Care Act-funded expansion of SBHCs in Tennessee, allowing for a long baseline period before the large majority of SBHCs opened. We will employ rigorous quasi-experimental methods with the linked longitudinal data to compare children in schools that gained access to a SBHC with those in schools without access to services provided by SBHCs and examine SBHC impacts on children’s mental health and educational outcomes, including by subgroups of children of color, children of immigrants, children living in rural areas, and those with specific health conditions. We will also advance our understanding of the mechanisms by which SBHCs may improve children’s mental health and education outcomes by: 1) elaborating and testing a child-centered conceptual framework for examining in-depth the organization and implementation of SBHCs and factors that constrain or enable their effectiveness; 2) undertaking a comprehensive documentation of the operations and services of traditional on-campus, school-linked, mobile, and telehealth SBHCs and filling gaps in our understanding of how they are operating in rural areas and through mobile/telehealth options, and 3) generating timely new information on how SBHCs adapted their service delivery approaches during the COVID-19 pandemic and the extent to which disruptions in children’s access to mental and behavioral health services disproportionately affected disadvantaged or underserved subgroups of children. We will actively disseminate the study findings to ensure that they inform program strategies, policies, and evaluation tools that state...