Very well written and I agree, "achievement gap" as presently used is bizarre and probably unhealthy. Are we going to examine the achievement gaps between all groups? It leads to ugly generalizations. That said, what such a phrase is MEANT to do is to create a metric of sorts, which in a way is what No Child Left Behind was meant to do (I know most people reading this are now angry). If we do not measure a student's progress (any student, all students) and if we do not have benchmarks or expectations, then we will leave a lot of good kids behind because we will not know (or care) that they are not achieving their potential. So by all means, let's get rid of the "achievement gap", let's stop testing as frequently, but let's NOT then open up (or exacerbate) the expectations gap. We expect YOU to succeed and will hold you accountable; we are not surprised YOU are failing and indeed we do not even see a need to measure your progress against some standard, who cares. That is much much more pernicious I think.