and haven't regretted it at all. DD has a Feb birthday and cutoff here is 12/1.
Taking her preschool teacher's advice we asked the school to have her tested about 5 months before K. She was 5 years advanced in reading, 3 in math, and 1 for social/maturity. They couldn't measure her IQ 'cause she hit the ceiling on the two tests they used. (Got this from DH, not me.) Armed with this info we were told she could not skip and start in first as it just was not done. Have they done any formal tests for you? I know public schools have to if you ask, not sure about private. You can pay to have them done but it is $$.
K was miserable. She felt so different from everyone else. She was dumbing herself down to fit in and it was heartbreaking. In May we met with the teacher that she would have for first grade. She was amazing, and had all these cool plans for DD. But after awhile we realized that she would essentially be doing the whole year by herself, making her feel even worse. We brought up our concerns, and she was placed in 1st the next week.
It took quite a long time for us to get her to understand that now the other kids abilities were similar to hers and she could stop acting dumb. I think academically she probably would have been fine by 3rd grade (where everyone can read fluently) but she would have been a mess by then. Now she is in 9th grade. She is in 11th grade math, and honors levels for all other classes. She has a 94 unweighted GPA. She won't graduate #1 in her class, as there are definitely kids more motivated, but she will be way up there. (If she keeps going like she is.)
Socially yes, there are kids more advanced than she is, but that would have been the case if she was still in 8th grade too. She has a close group of nerdy, smart, socially challenged kids. None of them are "cool" or care about normal teen stuff.
Driving might be an issue, but we'll deal with it. We weren't going to sacrifice her self esteem for that. And drinking in college? I went for 4 years and never stepped foot in a bar. Pretty sure I had a drink on day one and no one asked me how old I was.
The biggest problem we've had are expectations. She's "the smart kid". If she messes up (and she has) everyone notices. She's had some very rude comments made to her (mainly by teachers) if her work isn't flawless. That's a lot of pressure. She's had a few meltdowns where she said she wished she was "normal". I think that feeling would have been worse if she was not advanced. I imagine a lot of girls have felt that way at different times for different reasons.
In midde school on her birthday some friends decorated her locker. They made signs all over it that said, "13". Then one friend walked by that she's known since she was a toddler. She looked at the decorations and said, "Uh.. she's only turning 12."
Check out the Iowa Acceleration Scale and "A Nation Deceived" for more information. But honestly, in your situation, you are putting her where she is supposed to be, not really skipping a grade. Can she move up mid-year? As others have pointed out, in many states the cutoff is in December. She will definitely not be the youngest in college.
Good luck!
Oh yes.. I had a good friend who had a DD that was reading chapter books at 4 like mine was. DD compiled a nice list of books that are challenging enough for strong readers, but the content is age appropriate. We can e-mail it if you are interested. This was a huge challenge for us too. Her favorites at that age were "The Wizard of Oz" series and the "Little House" books.