In the United States, increased pressure through accountability policy and through the production and dissemination of scientifically based research are intended to create conditions for improving research use. Concurrently, researchers, education agencies, and funders have mounted efforts to strengthen relationships between research and educational practice to improve decisions about and outcomes for children. Accompanying these efforts is a need to understand, at scale, educational decision-making, and the role of research in it. To date, studies of research use in the United States have tended to focus on various stakeholders' research use (e.g., Biddle & Saha, 2002; Dagenais et al., 2012), case studies of schools or districts (e.g., Asen et al., 2013; Finnigan et al., 2013), or case studies of specific education policies or practices (e.g., Hopkins et al., 2019; Scott et al., 2017). The purpose of this report is to broadly portray research use in U.S. schools at scale to better understand where we are as an educational system in the more than forty-year journey to improve the role of research in education policy and practice. [For the executive summary, see ED628009. For the technical report, see ED628010.]