@noblegiraffe
Each individual class is a bubble and they are kept completely separate from all other bubbles which means the few cases we have had have been able to isolate a small group and stop the spread.
This doesn’t happen in secondary.
But it does in primaries, so we need to be looking to treat primary and secondary schools differently.
It is possible to make primary schools safer, to ensure measures are in place that do keep contact limited to small groups, ensure frequent cleaning and good hygiene, allow mask wearing. I know it is possible because DDs school do it and as a result have had very few cases and no cases where they have then spread outside the initial bubble.
With that in mind primary schools should reopen, with those measures in place.
Secondary is more of a challenge because of the structure of having different rooms/teachers for different subjects but there are reasonable and cost effective changes that could be made like wider mask usage, rota attendance to reduce numbers and increase distancing.
Having primary school children at home and pretending that they are able to effectively learn remotely is a joke, a 6 yo with parents working all day on their own computers/calls, cannot learn online by themselves. They can fill out a few worksheets on stuff they learnt before the school closed, maybe, but they're not learning new content or social skills.