depending of the maturity of the child I reccomend Tamora Pierce I love her and still read her books.

http://www.tamora-pierce.com/about.html

This is a link to the sumuries of her books, for the younger age I would reccomend the Circle of Magic and The Immortals. All the books have female main characters in the majoritiy and generally defying the social norms as well. The books do have a fair amount of violence that is dealt with pretty well.

hope it helps
kay :)