It is certainly possible for quite a few kids in a school district to be at or above 95th percentile. Since educated professionals tend to live in communities of folks similar to them, you can get a number of 95th+ perentile kids. In my eldest's class, the average SAT score for her class was an 80th percentile score nationally.
Of course, you won't have lots of 99.9th percentile kids anywhere in a public school (or even a private one, but some have a number of HG kids - at least the ones near us).
Good luck, but don't get too worked up. My eldest knows a few PG kids that did not skip. While school wasn't ideal for them, they are all happy in college. The one that weathered the K-12 years the best was really involved in a lot of activities, as schoolwork didn't take much time for him - he was in band, an academic quiz team, in student government, played a varsity sport, and did research with a local college professor (among other things). And he looked forward to and enjoyed the normal HS rites of passage, such as the prom. Advocate for her, but don't get upset if things don't work right now as you had hoped - there are lots of things to explore, even if some are not academic.
