The Learning at Scale study was designed to identify existing early grade reading programs with demonstrated impact on basic skills at scale and to conduct in-depth investigations of these programs to determine what makes them successful. After an extensive search, eight programs (spanning seven countries) were selected for inclusion in the study. Research on these programs has been conducted in order to answer the three overarching research questions, focused on understanding the components of instructional practices, instructional supports, and system supports that lead to effective instruction. Learning at Scale data collection activities for some of these programs were delayed due to COVID-19. However, with demand for information about how to implement effective interventions at large scale at an all-time high, we believe that the timely sharing of findings from Learning at Scale is essential. Accordingly, this interim report provides preliminary findings from our study to date, highlighting key high-level findings across all eight programs, as well as quantitative and qualitative findings from primary research for select programs. The Learning at Scale study is led by RTI International, as part of the Center for Global Development (CGD) education research consortium, funded by the Bill and Melinda Gates Foundation.