Judging schools by advanced scores

Jay Matthews:

Journalists like me get into ruts. We pick one way of describing data and stick with it. I tell myself that I would confuse readers if I made changes. That might be an excuse for laziness and lack of imagination.
A habit I share with many education writers is presenting school test results one way: the percentage of students who score proficient or above. I ignore a subset of that proficient group, the percentage who achieve at the higher, advanced level.
The advanced percentages are impressive in the Washington suburbs, because they have some of the highest average family incomes in the country. The District is different. Most of its public school students are from low-income families. But I have been noticing some D.C. schools with impressive percentages of students scoring not just proficient but advanced. What would those schools look like if we reported that higher order of achievement? In the long term, don’t we want as many students as possible to be learning at the advanced level?