since beginning of Sept. we have made it through so far with only 1 'close contact' scare between my 2 kids where a classmate kid starting showing symptoms, stopped going to school and then tested positive a few days later. 4 kids in the class (of 14) were deemed close contacts and had to q-tine for 10 days and do in-home learning. none of those kids got c-19 nor the teacher.
The younger one's teacher q-tined herself 2 separate times due to being a close contact to a positive case outside of school and taught from home with another teaching filling in at the classroom.
all in all, not too bad and what they are doing at school seems to work to mitigate spreading any positive cases that showed up to school. they wear masks the whole time and I think they have partitioned eating areas or ate in the classrooms (or outside during good weather), but not partitioned in the classroom; just spaced out as well as they could. The class sizes were already kinda small, but i think 85% or so elected to send their kids to in-person classes.
would the results be different in a classroom crammed with 30 kids? maybe. would i personally want to test out that theory, nah. so i don't automatically condemn teachers for not wanting to be in that environment day in day out.