Ha, my daughter loves the fairy chronicles right now, and those wild Lexile levels scared me for a minute when I saw them (she's four). I think certain things in their formula are weighted just so. It's tricky finding good reads! DD is t ready for more developed, involved books quite, but if she doesn't have a good read it RUINS our bedtimes/mornings (she likes to read in bed). So I've been hunting a lot lately. She was reaching the end of the rainbow magic series and the library only has two flower fairy books. Anyway, one thing I really like is the accelerated reader search-- it specifically says interest level, so anything "lower elementary" but higher reading level has been spot on.

Also a girl I went to high school wig wrote the girl who circumnavigated fairyland! I can't wait til DD is ready for it.