[Kate*]

It depends which level of school you're talking about. The older you get, the more common it is for people to be a year older or younger than you and the less of a difference it makes. It also depends when your birthday is; if you just miss the cutoff for Kindergarten, you'll be the oldest vs if you just make it, you'll be the youngest. I've also heard of parents delaying the start of school for their kids due to their maturity level rather than age. It's not that weird anymore. People might wonder why, but a person wouldn't necessarily stick out like a sore thumb.