DS is only 2, but I know that he is very shy and reserved (like me) and he is very soft spoken as well. He is super clingy and whiney and it's "mummy this, mummy that". We do playgroup and gymbaroo and I can tell from observing the others that are his age, that he is no where near as mature as them socially/emotionally. I wonder if he will change dramatically in the next year? But I doubt it. He has also never been away from me so I think 3 yo kinder next year would probably stress him out too much.
FWIW my March boy was exactly the same. In fact at the age of 2, he would refuse to have anything to do with other children his age LOL. He would wait until play equipment was clear of children before venturing in there. At music he would cling to me, not participate in singing etc.. he would play the big drum tho Then at the age of 3 it was like a switch was turned on. And he started to open up socially. 2 days of 3yo preschool did him wonders. He started Kindergarten (big school) this year, and there is just no way he could have been held back (just like Onyx). I've had a chat to his teacher about various things, he was definitely very ready for school, so no issues there, he did say that we might hit a few bumps along the way socially because he's one of the youngest, one of those bumps at the moment is the tiredness that comes from the effort of school. There are 6 yr olds in his class and he's only just turned 5, but he's doing just fine Going by the birthdays at preschool, majority of the kids were turning 5 in the 2nd half of the year, so really were probably only 6mths older than him.. not all of them are going to be significantly older, if that makes sense. I completely agree that the decision needs to be made closer to the time rather than now at the age of 2. When you think about it, all the Nov/Dec babies won't have a choice of when to start.. that's only 2/3 months older than your DS. So I wouldn't go in believing that he'll be completely surrounded by 6 yr olds if he starts at 5