No it has not happened universally around the world, some countries only had the initial shutdown in April 2020 and then the schools were open again. See here

No it has not happened universally around the world, some countries only had the initial shutdown in April 2020 and then the schools were open again. See here https://covid19.uis.unesco.org/global-monitoring-school-closures-covid19/country-dashboard/ https://covid19.uis.unesco.org/global-monitoring-school-clos... France and Switzerland as an example.