S.R.
There are things that are adult, and then things that are just good hygene.
Deoderant, shaving, and etc. are hygene. Yes, you should teach her how to shave and give her the time and privacy to take care of herself like a young lady needs.
Next comes hair products, training bras, and pierced ears. You remember the stages.
I definately would not deny her the things that make all of us comfortable and beautiful as women. Just put a cap on it at extremeties like make up...
By thye way the new razor "Intuition" has the shaving foam in a kind of soap bar around the head of the razor. I have sworn by it since I discovered it, no razor burn or nicks ever. I think it would be great for a young girl.