Building on the empirical work of the previous two studies, this paper describes the development of the Minds In Motion curriculum (MIM), as well as the setting and circumstances of a randomized controlled trial conducted to evaluate this intervention. Throughout this paper the authors emphasize the benefits and challenges of assembling an interdisciplinary team of researchers and practitioners from disparate fields into a team focused on developing a mature intervention. The Minds In Motion curriculum was evaluated as a component of the WINGS for Kids© after-school program located in three schools in North Charleston, SC. WINGS for Kids© is a structured after-school program that serves socio-demographically disadvantaged elementary students for 3 hours daily. The WINGS for Kids© curriculum emphasizes social and emotional learning (SEL) objectives through large and small group activity sessions that follow a regular schedule at all WINGS schools. The schools and communities that are served by WINGS have high levels of social, economic, and academic risk. The children who participated in the MIM study were kindergartners and first graders recruited from the WINGS program in three schools in North Charleston. Tables and figures are appended.