While the COVID-19 pandemic disrupted educational learning, the impacts of the pandemic may vary based on student demographics. The main purpose of this study was to determine if there were differences in student performance due to COVID-19 across several demographic variables. Multilevel mixed effects models compared the effects of COVID-19 in a large-scale math and English Language Arts (ELA) assessment for sixth grade students. By creating a cohort variable pertaining to the 2019 (pre-pandemic) or 2021 (post-pandemic) assessment, a single model was built with all 2019 and 2021 data combined. Interaction terms between the cohort variable and covariates allowed for comparison of covariates between cohorts. Coefficients from the 2021 covariates were compared to the 2019 covariates to understand and identify how changes in academic instruction due to COVID-19 may have impacted student learning. Results showed that assessment scores in 2021 were significantly lower than 2019 with math scores showing the largest decrease. The greatest decrease in scaled score between the 2019 and 2021 test administrations is seen in students who identify as female, Black, economically disadvantaged, and English language learner. ELA results showed that rural schools scored higher than city schools in 2021, and math results showed that suburban, town, and rural schools all scored higher than city schools in 2021. There was no significant difference in scaled score between public and private schools in either 2019 or 2021.