We've had our kids at large daycare centers all summer that are set up like in school environments. They haven't worn masks or anything additional and we've had no big outbreaks.....
You're correct, however I think the data is showing pretty clearly that the 0-10 age kids don't spread at a rate near that of adults. However, the 10-20 age range does spread at nearly the rate of adults. There are several cases of summer camps that did have big outbreaks in this age of kids. But in all reality it doesn't matter if it is a "big outbreak" or not. If someone in Johnny's 1st grade class tests positive, regardless of whether those kids transmit well, at a minimum that class is going to to be disrupted by quarantine. There just simply isn't a way around this and that is why I say it will be a roller coaster no matter what. And with older kids who do spread more effectively, and who won't be kept in class size cohorts, will have more disruptions I think. I "hope" I am wrong, but that is what I am preparing for. It is going to be a challenging school year for students, parents, and teachers.
The other thing I will say, at least in our community, is that we are just now getting to the point of substantial community spread. I believe the shutdown worked and we kept the disease away. Hindsight is 20/20, but at least in my area I think we could have finished school in person in the spring. There just wasn't enough virus around to cause us huge issues. But, it is here now with rapid increases in cases, not to mention a couple hundred thousand out of towners in the area right now. We're just now getting to the point of substantial spread, not unlike NY was when we shut down. Isolation has helped us, but like most new things it takes a lot longer to get to us.
Oh and sub are a huge issue in our area. And even more importantly, para-professionals. Most all of the schools in the area have huge shortages of paras and that will have a HUGE effect on the classroom and learning. Lots of older folks in these jobs just don't want to risk it. All my usual subs have said they are out this year, not going to be doing any subbing.