@MsFriz - Thanks for the book recommendation, I'll pick it up soon.
@Cricket2 - I know what you mean... The school they're at now will let him continue to 1st grade, but there are several issues we have with the school (hence the reason we're looking elsewhere). The public schools will let him go to 1st grade since he's completed Kinder at their current school. We are looking at a charter school that isn't "age based", but the lottery isn't until mid-March. We'd prefer to stay with private schools, and this one that we have applied to is the only one we can afford (other than where they are now). My kids are height challenged (and probably will always), everyone in the family is small...

@Grinity - Thanks for the advice, I'll check out the boards other threads to find some more information. I know that he's reading at a 2nd grade level, but other than reading I don't know what grade level he's on. As for the sports, I'm not worried about that at all. I was a swimmer and my husband is a runner. And he's into golf now, so none of them require excessive height.

Thank you to everyone who replied, I appreciate it!