Anyway, if some of these kids are not placed in the gifted program, and some are, in the long run they will have very different achievement, but all these kids IQ's probably hover around 115.
I'd be pretty careful about making this assumption. I really can't imagine how one would know such a thing. I have known some friends' kids since birth and I still wouldn't hazard a guess as to their IQs.
Also, in my experience, reading "by 4" is pretty unusual. My daughter read as a late 4 and we knew absolutely no one else locally whose child was reading at that age. We run in highly educated circles (most of our friends have master's degrees or doctorates), though not wealthy, super-achiever ones. I think there are lots of things you can hothouse, but I don't believe fluent reading before 4 to be one of them.
That said, I think it's certainly possible for parents to mildly improve IQ through enrichment. I have also read that any reading at all will cause a child to score highly on some of the IQ tests given to preschoolers. I can see how this might give a false impression. My DD was given an oral test requiring no reading (the RIAS) when tested at 6.
