I think this is the article we discussed in another thread. If so, I dug into it pretty closely.
The school district set the cutoff for the gifted program at the 70th percentile. So the students near either side of the cutoff would have been average students. So they're comparing average students in a gifted program with average students not in a gifted program. Gifted ed is supposed to be for gifted students, and they failed to make the correct comparison, yet they're drawing a sweeping conclusion about gifted students from it.
If you put average students into classes designed for above-average or better students, it's no surprise (to me at least) that they won't get much benefit. The material is probably too hard or the pace is too fast.
