Personally, I think it would be wonderful for my DS8. My PS does not do tracking in the elementary, although they do start to offer advanced classes in 7th grade. I would hope that the teacher could move the higher class through the easier material at a greater speed, thus spending time going into the material at greater depth. It would be great to challenge the kids who were more advanced. Our principle has agreed to unofficially cluster several of the academically gifted boys in DS8's class, in order to give him some peers. But I got the impression that she was doing so very quietly.
However, the politics of such a plan seem horrific. All of the parents would demand that their little prince or princess should be in the top class. And then you begin to discuss how they measure such giftedness, and if it has any socioeconomic bias to it. (We live in a community that does not have a whole lot of kids who are learning english as a second language, and other such problems.) And the kids who are in the "dumb" class would feel awful. So, again, personally it would be great... but I understand why some school administrators would cringe at the thought.
On a personal note, I really did not like school growing up. I was terribly bored. My teacher in sixth realized that I understood everything in the math textbook and allowed me work all the way up to geometry completely on my own. (Of course, I invented my own rules for geometry, which worked about 90% of the time and failed spectacularly the other 10%.
I therefore was rather confused when I reached real geometry. The perils of allowing a child to teach themselves!) But I digress... I moved at the beginning of 7th grade to a school which had tracking for gifted kids. From 7th grade on, I was completely grouped for all subjects with other gifted kids. It was heaven, and for the first time, I fell in love with school.
Tough call.. I can see both sides of the issue. A clever school administrator should invent a title for each of the sections... gifted kids, kids who excel in art or drama, kids who excel in spitballs...
