My son is almost 7 and just finished first grade in the public school. We are skipping him to 3rd grade in a private school. He is a a bit immature but we think he can handle the skip better than he can handle being bored in 2nd grade. The director of the private school thought he should skip to 4th. I would NOT skip him to 3rd in OUR public school, though,for a variety of reasons (class size, NCLB testing, ...). We also have heard the "he's a late summer birthday, he's not mature enough" argument.

Don't know if that's much help but wanted to let you know we are going through the same thing. Also, someone on this board pointed out to me that you can always DEcelerate if you need to do that.