When is the book most Exiting? Can you give me a cunclusion of the book and what the message is in the book

The first part of your question calls for an opinion. There is nor right or wrong answer.

The novel concludes with an article about a helpful, young, do gooder who shoveled the parking lot at school. Greg was the do gooder, although, he did it for himself.... not the school.

The novel's message is that even though we all excercise bad judgement at times, it's better to take responsibility for our actions than to run away from them.