Education Week (secondary source), Education Week, 'Map: Coronavirus and School Closures in 2019-2020' (Mar. 6, 2020; updated Oct. 13, 2021) (Ex. ECO-B-050)
Ballotpedia (secondary source; student counts from NCES), Ballotpedia, 'School responses to the coronavirus (COVID-19) pandemic during the 2019-2020 academic year' (June 30, 2020) (Ex. ECO-B-105)
Ballotpedia (Lucy Burns Institute), School responses to the coronavirus (COVID-19) pandemic during the 2019-2020 academic year (State-by-State closure chronology) (June 30, 2020) (Ex. SEC-15-001)
Ballotpedia, School responses to the coronavirus (COVID-19) pandemic during the 2020-2021 academic year (State reopening regimes, mid-year closures, return orders, monthly status) (June 30, 2021) (Ex. SEC-15-002)
Ballotpedia (secondary source; Burbio data), Ballotpedia, 'School responses to the coronavirus (COVID-19) pandemic during the 2020-2021 academic year' (July 8, 2021) (Ex. ECO-B-106)
Education Week (secondary source), Education Week, 'Which States Banned Mask Mandates in Schools, and Which Required Masks?' (Aug. 20, 2021; updated July 8, 2022; last data May 23, 2022) (Ex. ECO-B-117)
Ballotpedia (secondary source), Ballotpedia, 'School responses to the coronavirus (COVID-19) pandemic during the 2021-2022 academic year' (Aug. 1, 2022) (Ex. ECO-B-107)
Ballotpedia, School responses to the coronavirus (COVID-19) pandemic during the 2021-2022 academic year (school mask requirements and bans, staff and student vaccine requirements, litigation) (Aug. 1, 2022) (Ex. SEC-15-003)
