The purpose of this technical appendix is to share more detailed results and to describe more fully the sample and methods used in the research included in the brief, "Learning during COVID-19: An Update on Student Achievement and Growth at the Start of the 2021-22 School Year." The goal of this brief is to summarize student achievement and growth trends at the start of the 2021-22 school year so that educators and policymakers are equipped with the evidence necessary to guide decisions and make adjustments where needed as part of COVID-19 recovery efforts. [For the full report, see ED627550.]