The National Summer Learning Project (NSLP) examined the implementation and effectiveness of voluntary summer learning programs developed by five school districts—Boston, Massachusetts; Dallas, Texas; Duval County, Florida; Pittsburgh, Pennsylvania; and Rochester, New York—and their local community partners. The study spanned three phases. The RAND research team (1) collected formative data for strengthening the five summer programs in 2011 and 2012; (2) examined student outcomes after one summer (2013) and after two summers of programming (2014 and 2015); and (3) examined student outcomes in spring 2017, at the end of three school years after the second summer of programming. This seventh report in a series summarizes the findings of this third phase in the context of earlier findings and offers implications for policy and practice. Overall long-term findings show that, by spring 2017, the academic benefits for high attenders decreased in magnitude and were not statistically significant—although when benchmarked against typical achievement gains at the same grade level, they remained large enough to be educationally meaningful. (author abstract)