That was a pretty easy fun read. I can see why the kids at school are loving having it read aloud to them. The writing style is very well suited to kids who are beginning to understand sarcasm and dry humour. There are quite a few opportunities for open discussions on bullying, peer pressure and trying to find your place in a group dynamic. I would have thought the ideal age for this book would have been 10-13, but my daughter said her 9-10 year old class absolutely loved it. In fact they used part of the book in a school play. 
 The last part I want to mention, from a readers point of view, I really enjoyed the way there story all tied together at the end. My daughter said the whole class 'loved' the ending when they all had a "Oohhhhh" moment. I think it gave them something new to think about in their own writing.