Czechia doesn't have multiculturalism so it therefore doesn't have this concept.
So that would be all our schools. :) (Czechs and Vietnamese, respectively)
> and children who will not be disruptive in class
In my experience that seems to depend more on the type of school rather than on location. Gymnasia would be expected to have better-behaved students than vocational schools, even if the students come from the same region. I suspect that has a lot to do with entrance examinations. If you can pass the entrance examination for a Gymnasium, you're much less likely to be someone who had been disruptive in class in the past, and consequently also not likely to be disruptive in class in your new school.
Do Czechia have social classes? If yes do they live in different neighborhoods?