My students loved this story. Many of them have imaginary friends. The idea that an imaginary friend might actually be real was a little mind-bending for them. Quickly following whether or not a pretend friend could be real was whether or not ghosts are real. In true Mac Barnett style, the book really captured them. It was a big hit. We're really looking forward to reading it to our reading buddies!
The fact that the little girl in the story can see the ghost because she believes reminded me of Jeremy Thatcher Dragon Hatcher. There's a lot to be said for believing!