I would highly recommend the Sisters Grimm series. Very strong young female main character and incorporates every possible fairy tale character as modern day real life characters in the story. Also The Westing Game, the Penderwicks (there are several of these) and the All of a Kind Family series. I second the Mysterious Benedict Society - awesome for little gifties since the main characters are all pg kids. How about The Little House books? My DD enjoyed the first few in the Anna of Green Gables series but lost interest as Anne grew up, got married and had children.
