I love the books Escape from Mr. Lemoncello's Library and Mr. Lemoncello's Library Olympics (which just came out this Tuesday! LOL) by Chris Grabenstein, but they are surprisingly unpopular. I don't know why, though; they are great books and aren't old at all. If you have read either of them, please respond to this post! If not, I have a link to where you can buy the books or look at a sample on Amazon.

Escape from Mr. Lemoncello's Library: This link
Mr. Lemoncello's Library Olympics (read second, not first) Ths link :)