As the mother of a DD9 who just finished 5th, I'm going to join in with the others that you hold off on the homeschooling idea. Your DD seems to have what we all wish for our kids: learning new things in an environment that she likes with people she fits in with and is good friends with. What's not to like? While you may be worried that she's going to grow up too fast, your DD is who she is, and who she is is a 5th grader going into 6th. From what you post, that is who she is through-and-through, save for her birthdate. Your DD clearly has so much in common with her friends. And her friends aren't going to all of a sudden become inappropriate for her to be friends with. And neither are all the other kids she's in school with. If they do, then her fit may no longer be so great, but until that happens (if it ever does) I, personally, don't think you should undo her skip.
Also, keep in mind that you, as her parents, are there to help shepherd her through any difficult or awkward times growing up. No matter what grade she's in, she will have these awkward times. Keep in mind, too, that kids grow up and mature at different rates, both socially and physically. There is often a window of 2-3 years when these changes happen, and your DD is comfortably within this window as compared to her peers. Just because someome is the same age as all her friends does not mean that she will mature at the same time or rate as her friends, and the opposite is also true.
