Shifting the blame for low scores onto the teachers SUCKS.
Teachers are in no position at all to help their students when their parents are too damn poor or high to ensure an environment in which their children can actually learn.
Ok, so what is your suggestion for making the parents less poor or less high? General and baseless comments like these do not contribute positively to the collective conversation.
Choose another metric to compare schools/teachers (next to impossible), or factor in the "poorness" of the students/their parents. E.g. a rich, clean white hood gets higher thresholds for A than a poor black hood filled with junkies and violence.
This is not perfect either, but a rich/poor offset allows for a far better comparison.
Teachers are in no position at all to help their students when their parents are too damn poor or high to ensure an environment in which their children can actually learn.