Ugh.... well, I guess that I'd try to address the underlying social reasoning
Agreed. Find out the real, core, underlying cause and work from there.
Sometimes you just need to let them have a voice. My DD9 was passionate about applying for the gifted math program (to which she was accepted - yay!) ...but cringed at the idea of applying for the gifted language section (which she likely would have qualified for as well). I could have pushed it, but I decided to let it be... I don't want her to lose her passion for learning by forcing her into acceleration that she's not interested in.
So... is your daughter turning down acceleration because she really doesn't want it? Or is the social element standing in the way of something she actually does want to do? You need to be clear on which it is before you can proceed...
Good luck
