I don’t know if my school is typical, but just with this policy there’d be a lot of teachers and staff who would need to be replaced. School bus drivers, kitchen staff, janitors, guidance, teachers, aides, etc. Not everyone teaching or working in school is under age 50ish and healthy. We have those close to retirement, cancer survivors, and folks with other health issues like diabetes, etc.
It’s only the kids who are uniformly young - and some of those have health issues too.
If you want your school to open, perhaps you could offer to take the place of someone who shouldn’t be working to help out.