My DD's current school I believe uses that grouping method.
It also sounded like they knew what they were talking about, and I think for most kids they're on the mark. The problem with the cluster grouping is if your child is well past the level of the "highest" cluster in the class. Your child must be in that group because "there is no such thing as a group of one" as I have been told. Which is logical. But that means your little outlier has to stay at the pace of maybe the more advanced or MG kids in the class, and as you know there are large differences in kids as you go up the standard deviations.
Your little DD who does not like to repeat or sit still sounds alot like my DD. The sitting still part comes with maturity but the hating repetition doesn't go away...perhaps they learn to tolerate it better but they still get bored, frustrated, depressed or other.
Making friends takes a long time so you'll have to just keep saying that to the kids. If there is a summer camp they can take there are the same kids for the whole duration and if they seem to have bonded with someone when they are released at the end of the day maybe you can try and make a playdate in a public place with their mom/dad/whoever takes care of them during the day.
Trying to get kids playdates when you're new is sort of like dating!!! YOu just have to keep meeting people and trying
LOL
