Poor nutrition and insufficient amounts of physical activity are key contributing factors to childhood obesity and can adversely affect the physical, social, and emotional health, along with the academic success, of today's youth. Comprehensive school-based initiatives, in combination with broader community efforts that target these behaviors, can help youth to develop and sustain healthy lifestyles through the adolescent years. The Whole School, Whole Community, Whole Child (WSCC) model emphasizes the connection between health and academic achievement and highlights the importance of school wellness assessments, stressing that schools serve as the nucleus in providing these supports with input, resources, and collaboration from the community. Inadequate amounts of attention have been given to the process of conducting school wellness assessments that promote collaboration between university research teams and key school district stakeholders. This article presents the process of conducting a district-wide wellness assessment with the WSCC model as the conceptual framework. It outlines practical steps for other districts to replicate and key collaboration principles, along with the specific use of a unique wellness assessment tool that includes a readiness for change component. It also discusses challenges and opportunities encountered, lessons learned along the way, and implications for school administrators and school health practitioners.