“…For mathematics, effects varied between +0.20 SD and -0.19 SD (Mdn = -0.12 SD), with seven studies reporting a negative effect (Clark et al, 2020;Depping et al, 2021;Engzell et al, 2021;Maldonado & De Witte, 2020;Schult et al, 2021;Tomasik et al, 2020) and three studies reporting a positive effect (Gore et al, 2021;Meeter, 2021;Spitzer & Musslick, 2020) of COVID-19-related school closures on student achievement in mathematics. For reading, the effects found varied between -0.29 SD and +0.04 SD (Mdn = -0.14 SD), with six studies reporting a negative effect (Clark et al, 2020;Depping et al, 2021;Engzell et al, 2021;Maldonado & De Witte, 2020;Schult et al, 2021;Tomasik et al, 2020) and one study reporting a positive effect (Gore et al, 2021) of COVID-19-related school closures on student achievement in reading. For French as a foreign language, one study reported a large learning loss of 0.30 SD (Maldonado & De Witte, 2020), while another study reported an increase in correct solutions within a French learning program (van der Velde et al, 2021) during the COVID-19-related school closures.…”