> How does the existence of private schools enables this thinking?

Here is a simple example. There is a family with a combined 6k income, their expenses are 2k on rent and 1.5k on child private school, grocieries etc account for 500, savings another 500 and the remaining 1.5k goes on taxes.

Now the goverment proposes a 10% tax raise to improve public schools. Do you think this family would vote for or agaiinst that bill?

Now lets propose a counter example. Same salary, same expenses minus the private school, which gives the family 2k of savings per month. Now due to shortages in public schools they have volunteered at their kids school, helped with field trips, met other parents and families in their neighbourhood. Now the goverment does a 20% tax raise for public schooling. Would this family be more or less willing than the other family to vote yes?

By simply being involved you and your vote become resposinble for it. If you can pay your way away, specially if you stretch your finances to afford it, then investing in the system goes against your own interests regardless of the social externalities of your position.

We could have a society were parents of privately educated kids voted for a public school improvement, but psicologically and economically we know they by and large dont. Therefore the existance of private schooling comes at the expense of a fair, well resourced, and functional public education

Those who care about education, can leave to a private school instead, and not spend time trying to improve the public schools, just leave them to their fate: noisy school-is-boring kids sabotaging the classes for everyone.

Or that's how I interpret what GP said. Happening a bit where I live: richer families don't want their kids go to school in problematic suburbs.

> and not spend time trying to improve the public schools

> noisy school-is-boring kids sabotaging the classes for everyone.

It seems that those parents realize that if the system does not care about ensuring that kids in school actually learn things, then they better leave than trying to fix the kids of others (i.e., parents who does not care).

I would argue that it is a net positive for those public schools: those parents still pay local taxes while making sure that there are fewer students -> better student/teacher ratio.

Maybe depends on how hard or easy it is to improve the schools, on how much influence the parents can have? In Finland, apparently it was doable, but that's, in a way, a very different place than here.

I don’t that Finland is a good example: it is a small centralized country. In the US states can do whatever, so you can’t copy-paste finish approach.

There isn't much stopping individual states from adopting similar measures.

Well, they can't -- schools are funded by local taxes. Centralizing this across the whole state is a political suicide.

No, I'm proposing the opposite: that states try to act more like Norway/Finland by themselves, instead of hoping the federal government will do so (which isn't going to happen).

And yes, schools are funded by local taxes, but it doesn't have to be that way: if states really wanted to, they could take that power away from municipalities. The constitution gives the states broad powers to run themselves as they like.