The screening should be for kids unfit for being in public
We truly have a situation where the majority has to alter their ways in order to satisfy a tiny minority of the population. At a certain point, I think the public should be able to say:
"Stay home. Homeschool your kids. Make changes in your own life to deal with your own problems. Over here, the rest of us are going to go about our business."
This leads to the tyranny of the minority. Life does not guarantee a planet free of all risk. Why stop at the school? What about businesses and towns, products in stores, etc. etc.