Format changes in U.S. schooling in response to the COVID-19 pandemic varied by month and by school district, ranging from exclusively home-based to full in-person learning. The impact of these changes on adolescent schooling experiences, and the factors that mitigate such impact, have been challenging to quantify. To address these challenges we employed bi-monthly repeated surveys of youths (N = 6,546, aged 13-14 years) in a longitudinal study, starting before the pandemic peak (October 2020) and continuing through one year after the pandemic was declared (March 2021). We investigated how school format (in-person versus remote) impacted objective time spent on academic activities and the subjective experience of school, and how these were influenced by parental engagement. Periods of exclusive at-home remote schooling were pervasive reported by more than 60\% of youths and linked to a reduction in school enjoyment and time spent on reading, math, and science. In contrast, such per