The school my kids went to found that at the end of high school, class rank was pretty evenly divided between those who were identified at gifted and those who weren't. I think only around 10% were identified as gifted in elementary school and put into a one day a week pull out program.
When the school needed at make cut backs, they wanted to end the one day pull out. The parents of those "gifted" were outraged. How could they?
The most intellectually gifted students in the United States typically have little good to say about their schooling. Gifted children are usually bored and unengaged in school; they tend to be highly critical of their teachers, who they feel know less than they do, and they are often underachievers. In the best-case scenario, teachers recognize a student as gifted but, unable to teach at this level, they let the child learn independently. In the worst-case scenario, teachers fail to recognize a child as gifted and classify the child as unmotivated or even hostile.