I'm not seeing it but perhaps it would depend on the plan that is specifically being implemented at each school. How would you compare the risks to, say, grocery store workers, or any customer facing store front?
I can't speak from authority, of course. I'll just have to go with "it seems". It seems to me that the addition of the plexiglass makes a huge difference. While a cashier sees an awful lot of people in a day, there's a barrier during most interactions. A teacher normally comes quite close to students when looking at papers, or computer screens, when answer questions. The hallways are usually crowded. The students can't be trusted to follow proper mask protocol. Although the number of people encountered during a day is smaller, the duration of contact is longer.
I would hope there are people studying this sort of thing who could provide a lot better answers beyond the "it seems" variety. For me, that's the best I can do.
The other difference, when it comes to the focus on the decision making, is that the decision is a collective one rather than an individual one. The store will stay open or not, and then each individual gets to decide a lot about how they interact with the store (e.g. in store activity, curbside pickup, if available, and depending on cost). Schools are more of a straight up or down decision affecting everyone in lots of different ways, so there's a lot more focus on it.
Of course, exactly how much risk there is to teachers does depend a lot on what protocols are followed.
It's the kind of thing that you would think a government would be on top of, studying the problem, collecting data, presenting it in manageable ways. That doesn't seem to be the priority of our national leadership, and state governments have less ability to draw on resources, so like everything else, decision makers are left to scour reports from wherever they can. Even the CDC is somewhat suspect due to political pressure that we know has been placed on them.
I am hoping the planning is going well but it is still not even functionally finalized at this point. They are more or less pointing to full time, 7-8 hour days in front of a computer. What level of teacher interaction, how much parent side help will be required, and what learning foundation they are using is still not ready for parents to review.
Yikes. 7-8 hours in front of a screen doesn't seem possible, and I suppose there's a huge difference between high school and first grade. If a first grader has to spend more than a couple of hours in front of a screen, that means the parent does, too. You would be better off homeschooling.
One thing is certain. It will be a mess, and some school districts will do it better than others. I'm glad my kid is past high school.