When I taught in a "disadvantaged high school" in Boston, the metric by which the school was judged was not the average student score on the state's standardize

When I taught in a "disadvantaged high school" in Boston, the metric by which the school was judged was not the average student score on the state's standardized test (the MCAS), but the percentage of students achieving minimal proficiency. I think this is the same across the country. So the pressure is to keep pulling and pulling those last few students up over the bar. There is no fundamental incentive to help the kids that can already pass, because that has zero effect on the metric by which you are judged.