Over the past eight years, through examinations of school-administered reading assessments, Springboard has demonstrated internally that the average Springboard Summer scholar improves in reading during the program. Several partner school districts have compared Springboard scholars to their non-participating counterparts and found that, on average, Springboard scholars grow faster in reading than their peers. This promising evidence prompted Springboard to seek an external evaluation, with a focus on comparing Springboard Summer scholars to their non-participating counterparts. Building on Springboard's prior internal and district-led evaluations, this external evaluation is the next step on the path to validating Springboard's efforts at improving student literacy outcomes. This evaluation is a valuable opportunity to learn about Springboard Summer scholar outcomes by examining district-administered reading assessment data with select districts (those implementing Springboard Summer with efficacy). Additionally, it uses a rigorous methodology - propensity score matching, which controls for differences between students who get Springboard Summer versus those who do not. For these reasons, this study is an important extension of prior work. It serves as an external test of the Springboard Summer model, specifically focusing on districts where the program is implemented as intended, reducing the chance of findings being a result of poor implementation. This study's main research objectives are to determine: 1) How participation in Springboard Summer is associated with reading growth. 2) How Springboard Summer scholars' reading achievement compares to that of non-participating Springboard Summer students. [This report was prepared by the Springboard Collaborative with McClanahan Associates and University of Pennsylvania's ImpactED.]