Yes, the risk to kids is low, but they are unvaccinated so outbreaks can and do happen. Substitutes are hard to get right now in most school districts and if you have an outbreak and even 5 percent of the teachers are home sick it is a very real possibility there won’t be a substitute to cover. In my local school district principals and administrators are covering classrooms for sick teachers because there are not enough subs. Teachers would traditionally just go to school sick, because they don’t get much sick time and even if they are sick they have to write a lesson plan for the sub, but now what do you do? Do you go to school even though you have a cold that could be covid? Do you write sub plans for a sub that might not be there?
Bus drivers are also opting out because many are elderly and at high risk and the pay sucks so the risk reward isn’t there even if they are vaccinated. Same with lunch ladies, janitors, you name it. There is a staffing crisis in education right now. Teachers are burned out and those that can retire are at a higher rate than before. It is a mess.
So no, children, even unvaccinated, aren’t likely to have complications from Covid, but wearing masks in schools might help just enough to keep schools open and operating.