Reply #60: usually it means,

[mopinko]

pardon me for being blunt, but it mostly means black schools. that is the reality of a city that, while it has many integrated neighborhoods, is still one of the most segregated cities in the world. poor schools sort of covers it, but it is something more than that.
any teacher who has a few strikes against them, whatever they may be, is a lot more likely to get a job in a crappy school. there are some folks for whom it is a calling. there are some that are there because it is their hood. but mostly it is teachers who really, really need a job.

and down thread the comment about young and energetic, the other thing that they bring is a knowledge base that is something more than teachers colleges give you. science and math teachers are like hen's teeth here. you want to see a bullet proof teacher, it's a math teacher whose kids pass the test.