The final section of the novel begins with Auggie and his class preparing for their fifth grade nature retreat: this event will take place over three days and two nights at a nature reserve in Pennsylvania. Aside from one attempt to sleep over his friend Christopher's house -- a time when he got nervous and called his mother to pick him up -- Auggie has never had a sleepover before. This time, he is nervous, but excited too.
Auggie asks his Mom to buy him a new duffel bag, because the old one has Star Wars designs. He wants to try to shake off his Star Wars image, because in middle school you can be strongly defined by such hobbies. Mom helps him pack; Auggie wants to bring Baboo, his stuffed bear, for comfort. In the morning before he leaves, however, he changes his mind and removes Baboo from his bag, leaving the bear on his bed with a note to Mom. The note says that, if Mom misses him, she can cuddle with Baboo herself.
Luckily, Julian has decided that a nature trip is too dorky for him, and Auggie is happy that he does not have to deal with more of Julian's hostility. The Beecher Prep students move into their cabins and go on hikes through the woods for the rest of the day, then hang out by a campfire after dark. Auggie sleeps well and has a great time; he even writes a letter to Mom, Dad, and Via about all the things he and the other students are doing, though Auggie's family will not get to read his message until he is already home.
The Beecher Prep students go to an outdoor movie in the reserve the following night, and are joined by students from the other schools on the same trip. Auggie and his companions get there first and lay out their sleeping bags in front of the screen. The movie, The Sound of Music, starts and Auggie and Jack watch until roughly the middle, when Jack tells Auggie he needs to pee. They get up to find a bathroom. There is a huge line, though, so they go into the woods.
When Jack finishes and he and Auggie try to leave, they run into a group of older kids who smell like firecrackers and cigarettes. These kids shine a flashlight at Auggie's face and start freaking out, calling him Gollum and a lot of other names. Jack tries to confront them, but they do not let up, and the situation is looking bad until suddenly Henry, Amos, and Miles show up and tell the older kids to back off. As they start to walk back to the movie, the guy leading the older kids, Eddie, grabs Auggie's sweatshirt hood and yanks him to the ground. This starts a fight between both sides, and Henry pulls Auggie by the arm and tries to carry him away.
The Beecher Prep group keeps running until the older kids are far enough away. Henry, Amos, and Miles tell Jack and Auggie that they had seen the guys before, so they knew that the older students were there. Auggie and his companions realize that they have ended up in the cornfields, and try to head back towards the movie. Auggie's sweatshirt has ripped, but worse, he lost his hearing aids in the scuffle. Overwhelmed, Auggie starts to cry, and even Amos starts to comfort him.
Everyone talks about what happened on the bus home the next day, and everyone is concerned for Auggie. The nature reserve reimburses Auggie for the cost of the hearing aids; Mom fusses over Auggie when he gets home, but he is fine. They wait for Dad to come home from work with Via, and when he does, he brings a big surprise: a cardboard box with a little puppy in it. They name the puppy Bear. Auggie and Via stay home from school the next day to play with him, and Auggie remembers how they used to spend time together in this way.
When he goes back to school, Auggie notices that things have changed. He is now known for his bravery in dealing with what happened, and Henry, Miles, and Amos now welcome him as one of them. Only Julian still treats him badly, but Julian's popularity has diminished because he missed everything that happened on the trip. Just before the last day of school, Mr. Tushman calls Auggie in to talk to him. Auggie's old, mangled hearing aids were found in Eddie's locker at his school. However, Auggie says he does not want to press charges.
Mr. Tushman surprises Auggie by revealing how much he knew about what was going on during the year at school, but praises Auggie for the way he handled everything and for being one of the school's top students. He tells him that Julian will not be coming back to Beecher Prep next year. Then, during their last English class, Mr. Browne instructs the students to send in their own personal precepts during the summer.
Fifth grade graduation is the following day; Auggie gets a haircut that makes him look more grown up. In passing conversation, Dad admits that he threw out that old astronaut helmet, rather than lost it. This upsets Auggie, but Dad insists that he could not stand to see it covering Auggie's face anymore, because while Auggie might not love his face, his father does.
All the students take their seats for graduation, and Mr. Tushman makes a speech about the importance of being kind, no matter where you are. There is a reading of the Honor Roll, which Auggie gets, and Beecher Prep announces other academic excellence awards, which Ximena Chin and Charlotte win. Summer wins the gold medal in creative writing, which makes Auggie very happy. The final award is the Henry Ward Beecher medal to honor students who have been exemplary in certain areas throughout the school year. This year, the school has decided to give it to someone who has shown great courage, kindness, and friendship. It goes to Auggie.
Everyone is so happy for Auggie, especially his fellow students. Afterwards, there is a reception, and Auggie's family congratulates him. They start taking pictures of him, Summer, and Jack, but eventually the whole class ends up coming over to take pictures with him, too. Auggie feels at last that everyone wants to be close to him. Jack's and Summer's families come back to Auggie's house to celebrate. As they walk there, Mom reaches down to whisper in Auggie's ear and thanks him for everything he has given them, and for being himself. She says he really is a wonder.
This final section ends the story in much the way it started: from Auggie's perspective. Though this novel has traversed multiple perspectives, in the end, Wonder truly is Auggie's story. It is thus important for readers to see the how much Auggie has matured over the course of his first year at school. In this section, it is evident that Auggie has grown up in many different ways, beginning with shedding his Star Wars persona and leaving behind something that was a part of him when he was a child. While Star Wars is still important to him, he recognizes that it is important to be known for other things.
Auggie's success at the sleep-away trip with his school shows that he no longer uses home as a crutch. He feels comfortable enough with himself and his friendships to leave the security of his family and set out on his own: in a classic bildungsroman, a character's ability to leave home is a sure sign that he or she has grown up. Of course, Auggie is still a child, so he gets to return to his family once the trip is over -- though now the other Pullmans are there as support, rather than as a security blanket.
The fight in the woods is a pivotal moment in the book, to a large extent because of the way Auggie handles it. Though the kids from the other school make fun of his face, Auggie does not let such insults get to him the way he has in the past. Even more important, however, is how Henry, Miles, and Amos -- kids who had previously been on Julian's side in the "war" -- now stand up for Auggie. This is a symbolic moment, because it shows that everyone in school who matters has accepted Auggie as one of their own. Henry, Miles, and Amos, and all of the other kids in school after the retreat is over, have learned an important lesson about judging someone before you get to know him or her. In this manner, they have all grown up as much over the course of the novel as Auggie himself has.
Not all the kids come around, though. Julian, the book's principal antagonist, still has not learned the error of his ways. But as a character, Julian relays an important message: some people will always be cruel, regardless of how hard other people may try to change that. But Auggie is not obligated to make space for someone as hostile as Julian in his life, and things end up working out in the end when Julian leaves Beecher Prep.
In any novel, a graduation is a symbolic event. At its core, a graduation is about moving on, moving up to bigger and better things: it marks the end of one stage of development and the beginning of a new one. Auggie has grown up so much over the course of his first year at school, and graduation represents the culmination of his efforts both to fit in at his new school and to accept himself as he is. The award that he receives is a confirmation of his efforts, proof that he has managed to overcome adversity, rise above immature opinions, and teach everyone the power of kindness and acceptance.
The novel ends with Mom calling Auggie a "wonder." There have been a lot of words used to describe Auggie in the book -- mean ones, like "freak," "Gollum," and "alien," as well as nice ones, like "funny," "smart," and "friend." "Wonder," however, is the most all-encompassing of the bunch. It captures the way Auggie has changed so many lives around him just by being himself. It captures Auggie's own inner power, the courage and kindness that allow him to rise above the cruelty of others. Auggie has become something exceptional by the end of the book, even though from his own perspective, he is just like everyone else -- a normal kid.