The purpose of this study was to explore the reading performance scores of elementary school students in one school district before and after school closures due to COVID-19. This nonexperimental, exploratory study of quantitative, archival data was designed to explore a single cohort (N = 2,006) of third- through fifth-grade students' i-Ready reading diagnostic scale scores from five different assessment periods: before school closures in spring 2020 and four subsequent assessment periods after face-to-face instruction resumed in fall 2020. The research sample excluded exceptional student education students and English language learners who had been retained. Mean scale scores of the research cohort were compared to the school district's 2018-2019 i-Ready norms and to the 2018-2019 i-Ready national norms for each of the five assessment periods. The results of the comparisons revealed that the research cohort's mean reading scale scores were significantly different from the district and national norm groups' mean reading scale scores. The research sample's mean reading scale scores were slightly higher than those of the target district's norm group; however, the mean scores and the effect sizes were small. The research cohort's reading scores were significantly lower than the scores of the 2018-2019 national norm group. Although the students in the research cohort demonstrated small increments of reading progress over time, the rate of progress was not commensurate with the 2018-2019 national norm group's rate of progress. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]