There are some families who choose to do this locally. I also know a few families with younger girls they tested to get into kindergarten early.
With the local push to all day, very academic kindergarten, I can't say that I blame some parents. Particularly those with young active boys. There were a couple bright boy's in kindergarten with late August birthdays that were shamed all year into "good" behavior by trips to the principle's office and time outs, etc. I'm not sure that's a good way to set up for a happy and successful school career. There was also one boy in my son's K&1st grade class that was older - July birthday. But was still struggling with reading even though both his parents teach at the college level and are highly engaged parents. So in his case, it was totally the right decision. It really depends on the kid and the kindergarten's and first grade's classrooms they are going to. On the other hand there was a boy in DS's kindergarten class with an April birthday held back reading a couple years beyond grade level who was acting out at every turn. He definitely should not have been held back
My October birthday HG+ son still had an adjustment to all day kindergarten. It wasn't horrible for him, but I wouldn't say he just jumped right in and loved it. Academically, it would have been fine a year earlier. Behaviorally and socially - not really. Half day would have been ok. It's hard to know. It clearly wasn't a good fit in many ways.
Our district uses the NNAT. Which is not ideal by any means, but it's normed by the month the child is born. So getting IDed as gifted shouldn't necessarily be affected by your birthday anyway. Although, it is affected by your ability to focus on a group test in a classroom clearly. They are still over IDing in some cases, and missing kids in other cases just using the NNAT though.
