Mercy Watson (ages 6+) Mercy Watson is a humorous pig that gets herself into all sorts of amusing situations. This 4 book series is perfect for those who are ready to start chapter books.
Ramona Quimby (ages 7+) It's just hard to be a little girl. From annoying older sisters to tight situations at school, Ramona handles it all with grace and spunk.
American Girls (ages 7+) there are multiple series about multiple girls, the little girl literary goodness goes on and on with these books. They are a fantastic way to get young girls hooked on historical fiction, and keep their attention for a very long time.
The Chocolate Touch (ages 7+) John Midas loves his chocolate, perhaps a little too much. His chocolate obsession gets him into trouble when he gains the ability to turn everything he eats to chocolate.
The Littles (ages 7+) There's just something entertaining about little people living in a big world. This series chronicles the lives of a family of tiny people living in a full sized world. More wholesome adventure for the whole family
Other books for girls that we've enjoyed:
Adventures In Odyssey - The Imagination Station series (ages 6+)