The Templeton Twins Have an Idea by Ellis Weiner (illustrated by Jeremy Holmes) as being a great book for kids who have outgrown the Diary of a Wimpy Kid series. Now personally I don't see how anyone outgrows that series, because it's hilarious and awesome. And I always have to wait until my kids are done with the book (three times) before I'm allowed to read it. (Yes, I could read it while they're in school, but I'm WORKING).
So this time I got The Templeton Twins book and didn't let my kids see it until I finished. And it's a hilarious, awesome book I highly recommend. The Templeton Twins are 12 year old and live with their awkward inventor/professor father (yes, a stereotype, and yes the mother is dead - another children's literature stereotype). They get kidnapped and have to get out of the situation (don't worry - it won't give your kids nightmares). Your kids will love how clever the protagonists are, and also the humor. You'll love the humor. Like naming the buildings at the university (Tickeridge-Baltock Institute of Technology, i.e. Tick-Tock Tech) Jerry Hall, Daryl Hall, Annie Hall and the like. The kids won't get that, but you will. The narrator has a very distinctive voice, and puts review questions at the end of each chapter. Unlike the review questions kids have to answer in school, these are - you guessed it - VERY funny and don't always have to do with the actual chapter.
About Weiner, he's written (or co-written) lots of funny books including Yiddish with George and Laura (Bush) whose very title is funny. The book is funny too - if you know some Yiddish. And a new one on my list: How to Profit from the Coming Rapture: Getting Ahead when You're Left Behind. Yes, he used to edit National Lampoon.