"Ranking high schools tells you which schools are rich or selective"

“College rankings, at least in theory, are responding to a need in the market. Students applying to prestigious, selective colleges — particularly students who have the academic qualifications and the financial means to go to college anywhere — have quite a few to choose from. Enter rankings, a way to sort through it all. Public high school doesn't work this way. The most useful information for you is what the best high school in your city, state, or school district is...Publications know they're mostly ranking on wealth and selectivity. It's why there are separate lists for schools that actually enroll low-income students in both the Daily Beast and Newsweek rankings. So why do it?
Because everybody loves rankings.” 
http://www.vox.com/2014/9/11/6123757/ranking-high-schools-makes-no-sense

This makes many very good points, and makes me cringe/giggle about how much we cared at my high school about our rankings.