In this report, we present a cost analysis of Raising Educational Achievement Coalition of Harlem (REACH), a partnership between Teachers College, Columbia University, and five high-needs schools in Harlem, New York City. A rigorous cost analysis can help illuminate the resources used to implement its theory of action, in addition to contextualizing the size of measured effects in a broader implementation framework and helping decision-makers select among alternative uses of scarce resources. REACH entails deep collaboration between schools and program staff in five key areas: Leadership, Teaching and Learning, Expanded Learning Opportunities, Physical and Mental Health, and Family and Community Engagement. The program supports schools in achieving their goals for student learning by utilizing university and community resources, including research from faculty, and graduate student assistants working as interns or volunteers in exchange for hands-on learning experiences. We used the ingredients method for cost analysis, documenting all resources utilized to operationalize the program’s theory of action regardless of whether each resource has a monetary cost or who pays for or provides the resource, in order to fully capture the economic or opportunity cost of the program. We obtained data on ingredients from program documentation, a detailed report on program implementation, and interviews and personal communications with program staff. In 2016-17, REACH cost $2,732,960, or $1,560 per student, with substantial variation by school site, domain of REACH, type of ingredient, and source of ingredient and associated funding. We supplement this analysis with a case study of the Teachers College Community School and sensitivity analysis. While the costs of REACH are substantial, the program itself is comprehensive and wide-reaching; further study should compare the costs of REACH to measured effects in a variety of areas, including student test scores, and behavioral, health, and socioemotional learning outcomes.