Teacher unions are too powerful and do not have the students best interest as a priority. They are very political and very liberal giving lots of money to Democrats. Teachers who don't support the liberal agenda may not want their money going to support liberal politicians. 

As the pandemic has revealed, even though all the experts and data say that schools are safe to open and children are at very low risk. Yet teacher's unions are refusing to go back even when billions of dollars have been spent to make schools safe. Do teachers not believe in science? What about all the harm done to students by keeping them out of school for so long? Depression & anxiety are up. Suicides are increasing.  Child abuse is on the rise & not getting noticed since children are staying home. Children who get breakfast & lunch at school are going hungry. Not to mention how much children are falling behind in school and how little they are learning. There are many social skills that can not be learned at home alone. More harm is being done than any possible good at trying to keep them safe from the virus.  Most teachers are under 50 and are at low risk. For teachers who are at high risk, they should be able to work from home if they want. Teachers are essential workers!!! People have been going to work at stores and other places for the whole of this pandemic. Private schools have been open and are doing well. There are going to be some cases but we can't shut down schools till there is zero risk. There is always some risk. Kids have a higher risk of the flu then covid. The overall recovery rate from Covid 19 per Web MD is between 97 - 99.75%.

There are many teachers who want to go back to school. They should leave the unions!  The Supreme court said teachers Do not have to be members of unions.