The COVID-19 pandemic caused in-person school closures around the world that impacted student learning and academic achievement to an unknown degree for all types of students. A majority of research on out-of-school time (summer vacation, absences, weather-related events) and initial research related to the pandemic indicated a negative impact on student learning and academic achievement. However, other research has found a lack of a negative impact and/or evidence of academic achievement, indicating the potential widening of the achievement gap. This quantitative comparative research study explored the impact of the COVID-19 pandemic and prolonged in-person school closures on student learning, as assessed through a comparison of student achievement on the New Jersey Student Learning Assessment (NJSLA), prior to and after the in-person school closures, and if that impact varied across the student subgroups of General Education, Special Education, Multilingual Learners, and Economically Disadvantaged and Non-Disadvantaged. NJSLA testing data for seventh grade students were retrieved from a large urban district in the state of New Jersey. Findings indicated that statistically significant differences existed between test scores in 2019 and 2022 for General Education, Economically Disadvantaged, and Non-Disadvantaged students. Findings also indicated that for this sample, the achievement gap shrunk as the variance between groups was smaller in 2022 than in 2019. The findings of this study offer District X and similar districts valuable insights into students and their education in a post-pandemic and post-school closure educational landscape. [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.]