Teacher Policy Research….
has a report out on teacher quality and New York City schools from 2000-2005. What this report found is that in 2005 teachers in the area were more equal across all schools no matter what the poverty level is.
They say in 2000 that highest poverty schools were on average 59 points behind on SAT scores to the lowest poverty schools and in 2005 they were only on average 39 points behind.