Catching Diamonds in the Rough

When i was growing up in canada, i never once took a standardized test. I completed my education without ever having one. So it's unclear to me what their function is. Originally the idea was that it was away to spot diamonds in the rough. But as you correctly point out, the the test has been gained so spectacularly by the upper middle class that its not really catching diamond in the rough any more. It's really catching kids who have been prepared for taking the test. And it turns out there'e probably other better ways of catching diamonds in the Rough.