My dad once said to me, "You give a lot of books three stars." I do.
This book was very easy to read and I was very bored at the time which are the only reasons I finished it. A couple of our children's librarians told me Grabenstein was rude to them when he visited our library for an author's talk (there was some miscommunication about the equipment he needed and he made some comment about not us being in Silicon Valley but not having the set up he wanted... I'm paraphrasing).
So that story does color my opinion of Grabenstein. I enjoyed his Mr Lemoncello books, but this one just didn't have the same magic/fun to it.