What helped me escape poverty was grammar schools (hated by the left)
The trouble with this is that grammars only ever helped 20% of kids, and over half of those in grammars were from middle class families, so that's a small percentage of kids being helped to escape poverty.
My dad was a miner's son and from a town where there were few options for boys apart from mining. He passed the 11+ along with one other boy in his year, ended up in a decent white collar job. Of the other dozen or so boys in his primary class who went to secondary modern, all but a couple became miners, then mostly long term unemployed after pit closures.
Grammar school changed my dad's life but he was always opposed the grammar system because he felt angry and guilty that he had (as he said) fluked the 11+ pass, at least 2 or 3 others expected to pass but didn't, and others might have been later developers. But none of them had much of a chance after 'failing' to prove themselves in one exam at the age of 11. And that was in the days before the 11+ tutoring industry. I've not seen stats for the areas which still have grammars but would be interested to know what percentage these days come from genuinely poor/working class households.
I do understand that it was a route out of poverty for some, but it also threw so many on the scrapheap at such a young age. This is why the left dislike selective education. It's nothing to do with resenting people for bettering themselves, it's because grammars are such a flawed system that can only help a small number. A good comprehensive school will get its brightest kids to the best universities, but also provide opportunities for less academic kids to develop the skills that will give them fulfilling lives too. But obviously that requires decent funding of facilities, buildings, books, equipment, staff, etc, which have been lacking in recent years.