Redwall is one of top-selling series right now, for the 9-12 age set. The boy across the street is not quite seven, and gifted, and he's really into it. I told my sister about it for my nephew, who just turned seven, and is also reading on a 6th grade level.
Right now, there are 14 books in the series. Parents who don't like Harry Potter for their kids, steer them to Redwall, which is set in Medieval times, with knights and action, but the characters are mice.
I asked the boy across the street about the book, and it was Matthias this and Matthias that. "Matthias the Brave!" If you're considering it, this would be a good time to name a boy Matthias.
PS I saw a movie yesterday, and a principal young female character was named Amelia.