The only way to fix that is with true school choice options. That way when parents realize it's a problem they can send their kids to schools that make a point to include it rather than the ones that leave it out completely.
That is, if every child getting a decent schooling is what you want.
It's the total lack of school choice that keeps people stuck in bad schools in the first place.
They complain about the work environment constantly and every single complaint is one that would be resolved by school choice. Every. Single. One. Yet they're all completely opposed to it.
Usually the entire reason for that opposition is fears of religious schools...which doesn't make sense. If there is that much opposition to religious schools that would mean that there's plenty of parents who would choose the non-religious options so again...a system which works itself out.
I have ONE friend who doesn't complain and that's because his teacher career has been at two of the best schools in the entire state.
I am extremely sure that would work OK.
Now, here's the thing: to end up with a highly rated school you need good teachers. Good teachers tend to gravitate towards the same factors that any other employee gravitates towards: pay rate and a good work environment. For a teacher, a good work environment usually means administrators who support them at all times - including dealing with parents.
Now this is a hugely important scenario to take into account. If a teacher is pressured by parents and fired by a public school currently...where exactly are they supposed to go? In a school choice scenario, they'd have multiple different options instead of many schools from one central authority. When teachers have more options and can simply walk out the door of a bad work environment with an unsupportive admin, they'll end up getting RECRUITED by other school administrators who know better.
Parents will continue beating down the door of those good schools to get in, but right now if a parent threatens a teacher, mouths off or pressures them for better grades they are doing so with no potential consequence. If you try that at a private school you know what happens? Parent gets a warning and if it happens again the child will have to find another school the next year. The admin isn't going to risk losing a great teacher to appease little Johnny's parents.
This shifts the ENTIRE dynamic of the school system to one in which teachers are in control because teachers are effectively the product.
Just think about what the job market looks like for programmers right now in areas with high demand. That's essentially what the market for teachers would become.