This is a tough one but I would say the climax of the story is the point where Philip breaks into tears because he can not sing the National Anthem and confesses he does not know it. At that point the conflict reaches the peak and ends. What the novel does not have is a resolution. That is the beauty of it, though, because it raises some great discussions in the classroom. It's tough to pinpoint the climax in this book since it's written documentary style so you are not getting a flowing story but bits and pieces.