I believe that responsibility falls to the states. As long as the state is treating is a health issue and is treating everybody equally, it is considered Constitutional as far as I know.
It’s stupid, but that’s how it is.
Apparently I mistakenly thought the decision fell to local school districts with guidance from the states.
Odd that no one (articles, I mean) cites law.
Nevertheless, with parents armed with facts, public opinion can prevail.