I'm all for equality of opportunity, which is why I'm so bothered by this, because high ability children deserve an opportunity to learn, too.
Yes, of course they do. Unfortunately, the educators I've talked with on this subject don't seem to care about the high performers because they're "already proficient." There seems to be no concept of the idea that someone proficient at third grade math might benefit from moving to fourth grade math while still in third grade. The idea just isn't there, and when I've mentioned it, I get blank stares or annoyance in response.