ABSTRACT Anxiety and depression in caregivers of children are the most prevalent mental health problems in populations in Sub-Saharan African (SSA) countries and are a major public health challenge for which broad management strategies currently do not exist. Caregiver mental health research in SSA has primarily focused on parents and not teachers despite high prevalence of anxiety/depression reported in teachers. In Uganda (the location of our proposed study), an estimated 28% of parents have mental health problems, and 25% of teachers have anxiety/depression. Intervention to address caregivers’ and teachers’ mental health needs remains limited, in part due to lack of resources and cost-effective population strategies. Thus, there is an urgent need to develop mental health interventions that: 1) improve both teachers and parents stress management and reduce prevalence of mental health problems; and 2) apply low-cost population strategies to improve accessibility of the interventions in the broader school system. This proposal seeks to test the feasibility (R21 phase) and effectiveness (R33 phase) of a new mHealth-App intervention, the mHealth Toolkit for Wellness & Empowering Lives of School Community (mWEL) in Uganda. mWEL-App is an interactive preventive intervention tool for teachers and parents as a self-help support modality. mWEL integrates three key mental health service functions: i) comprehensive screen to assess mental health (anxiety, depression), stress, and related contextual risks; ii) a tailored strength and weakness profile/report with recommendations to promote self- awareness and mental health knowledge; and iii) tailored evidence-based strategies and additional support and clinical resources to improve skills in stress management, emotion regulation, and maintain mental wellness. To promote accessibility and to have broader population reach, mWEL will be embedded in the education system and we will develop a sustainable approach to its implementation suited to local capacity and policy. Specifically, we will apply a community and peer-empowered task-shifting approach to develop a workforce for implementation. The Specific Aims are: (1) to build research and service capacity for digital and public health approaches to improve caregivers’ mental health in schools; (2) to test and enhance usability of the mWEL-T and P and to test feasibility and efficacy of both Toolkits in primary schools; (3) to test the effectiveness of the optimized versions of mWEL using a cluster-randomized control trial (cRCT); and (4) to identify big data analytic strategies for improving Digital-Toolkit decision support and precision mental health care.