For reference, Middlesbrough is one of the most deprived places in Europe (inc. Eastern Europe). I know people who grew up round there, I have been there quite a bit...it is unlike anything you see in most developed countries (the only place I have ever been like this was slum areas in Milan, and rural areas of Eastern Europe).
Even if schools had the teachers (most of them just don't teach some subjects, like computer science, at all...they don't have the staff, no-one will live there), bullying is off the charts, sexual violence against girls in school is an epidemic, teachers sexually abusing students is an epidemic...although hopefully ending...I would say it is close to impossible for most people in this situation to lift themselves out (particularly given the parents, not just school). I know people who went to schools around here, I know people who teach in these kind of areas in the UK...these places aren't developed country.
Btw, if you grow up in an urban environment in the South in the UK, even if the area is heavily impoverished...your school is top-tier. The issue is complex.