I think New Moon is a great magazine for girls. Depending on the physical/emotional maturity of the child, I would see it being for ages about 8-14.
I know the OP's child is older than the target age group, but we have a subscription to High Five (a younger kid's version of Highlights) and it is wonderful. It is very gentle, with a good mix of perspectives and something for all areas of development, like social, emotional, cognition. It has healthy recipes, simple crafts and stories. A very, very sweet magazine, my son loves it.