A design-based research study on the development of one-page tools to support systemic thinking in public managers is presented. Study participants included public managers of social and human service agencies within government or nonprofit organizations, as learners for whom the tools were designed; and instructional design professionals, offering expert opinions regarding the design of tools for adult learners. The design process consisted of generating ideas, visualizing ideas and developing prototypes of the tools. Formative assessments of tool prototypes were conducted in several small online focus groups, sharing specific tools to be used within the context of specific management practices, such as collaboration, culture development or evaluation of the organization as a system. In this article, we discuss the context surrounding our designs, the process used to design systemic thinking tools, experiences of a one-page tool design using design stories and lessons learned from design failures encountered during formative assessment. This study contributes to the body of educational design research by emphasizing the large learning gains achieved through the design of simple one-page tools.