The Spiderwick Chronicles - The Field Guide by Tony DiTerlizzi and Holly Black. I've been reading Harry Potter and the Philosophers Stone to Luke and I have been wondering what to read him next. I'd heard of The Spiderwick Chronicles, but had never read them so I bought the first one and thought I would check it out before I read it to him. Looks like a goer!
By the way, I just did a quick count, because I read a lot of children's books! I have read 23 adult books this year. Not bad!