The third book in the Diary of a Wimpy Kid series:
"...it's not easy to think of ways to improve myself, because I'm pretty much one of the best people I know."
Greg Heffley and his father are at odds - Greg is happy with the way he is, while his father is tired of his wimpy ways. If Greg doesn't do something soon, he'll be sent off to military school and lose his chance to impress the girl he likes!
Jeff Kinney - Diary of a Wimpy Kid: The Last Straw
Very Good Condition