The main characteristic of poor districts is that they’re poor, which means they don’t have the means to implement high pay schemes. Rich districts do.
The school district I worked in had impoverished students but high per pupil funding, which is pretty common. What reinforced the inequality in that district was that teachers who were able to, self-selected to have the best behaved students, who were most likely to see improvements in test scores. The teachers who ended up with 90% of their students starting the year multiple grade levels behind and with severe behavioral problems would rarely stay in the classroom more than 2 years.
You think of it in terms of inequality, which is one perspective. However, if seen from the perspective of the best behaved students, the ones who want a positive learning environment that will maximize their talents and success, this situation seems greatly preferable to the alternative, which is a sprinkling of problematic students disrupting the learning equally in all classrooms and making overall outcomes more mediocre. This is Ontario's public school system lately, in a nutshell.
Regardless of district the US spends more per student than most other countries.
The issue is that this gets eaten up by bureaucracy and teachers are left living in poverty, hence them clinging to unions like a drowning woman to a straw.
