Each time he got in trouble, he was warned to shape up because this was his last chance. Even the day he left for the island, several of those who gathered to see him off, including his parents, had warned him, "Don't screw up. This is your last chance." Cole braced himself for the next big wave. Whatever happened, he could always count on having one more last chance. (1.16)
Cole has no incentive to actually change for the better because he's always gotten away with his bad behavior in the past. Sure, he's received a slap on the wrist…but he's never gone to jail forever.
Edwin looked out across the bay and drew in a deep breath. "Years ago, I was brought here myself when my spirit got lost. This is a good place to find yourself." (2.28)
Even though Cole feels like he can't identify with the adults in his life, they're more similar than he knows. After all, Edwin and Garvey were both delinquent youth, too, once—they just underwent transformations into responsible, caring adults.
Edwin pulled out a key and turned Cole roughly around to remove his handcuffs. "Anger keeps you lost," he said, as he started back toward the shelter. "You can find yourself here, but only if you search." (2.30)
When Cole first reaches the island, Edwin and Garvey both tell him that this is the perfect place to find himself and become a better person. Too bad he doesn't take that advice to heart the first time around.
Garvey shook his head. "Banishment isn't a sentence. It's simply a time for Cole to walk his talk. We tell him to give more than lip service to the idea of change, but what chance does he have to prove anything if he's locked up?" (6.63)
The idea of Circle Justice is that they're not just going to punish Cole and lock him up. Instead, they're more interested in reforming him, making him a better person who's less likely to commit crime in the future.
The only person to speak in Cole's defense was Garvey. "I don't know what-all happened on the island," he said. "But there has been a change in Cole; of that, I'm sure. Whatever we decide to do, I hope this change is allowed to continue." (15.5)
Only Garvey and Edwin seem to believe Cole has changed after his near-death experience and that he might be reformed after all. They're even more confident in him than his parents are. Though to be fair, his parents aren't exactly his biggest cheerleaders.
Again, Cole knew he was lying. He had slept poorly because he had considered making a canoe instead of a totem. Taking a deep breath, he lifted the hatchet and began striking the center of the log. Again and again he hacked, until a deep groove circled the log. With each blow, he felt his anger disappearing. (21.17)
If Cole wants to truly change, he has to fight against all his usual instincts and take away the temptation to run away from all his problems. So he hacks up the log so he can't even contemplate escape.
"I started making a canoe, but I knew that was wrong, so I cut this deep groove so I couldn't try again. When I started carving the eagle, I finally slept good." Cole ended by telling about the eagle dance and what he had learned. "Are you mad at me?" he asked. (21.37)
Even though Cole was tempted to run away, he's still changed considerably, especially since he's willing to tell the truth and admit his mistakes to Edwin. He's not trying to cover up his bad parts anymore.
"There's still something missing. It isn't enough to be sorry and forgive. Somehow I have to figure out a way to help Peter. Until then, I'll never be able to carve anything in the blank space. That's what I had to discover before I could heal, wasn't it?" (24.7)
Over time, Cole realizes that despite how far he's come, he's going to have to work even harder in order to gain Peter's forgiveness and help him move on. He's going to have to somehow make it up to his victim.
"Cole," Rosey said, touching his bandaged arm. "In a few months your body will heal, but time won't heal your mind as easily. Helping others can help heal your wounds of the spirit." (13.45)
Even Rosey, the nurse who takes care of Cole after he's mauled by Spirit Bear, can tell that Cole is hurting a lot inside and that something needs to change in order for him to thrive.
"Your father isn't a bad person, but when he was younger, he had parents who beat him for everything he did. That's all he ever knew. When I saw him start doing it to you, I kept telling myself things would get better. Drinking helped me ignore reality." She shook her head. "It took a divorce and your ending up in the hospital to wake me up. I realized I couldn't change your father, but I could change me." (14.56)
Cole's always assumed that his parents will be emotionally distant and abusive toward him forever, so it's pretty gratifying when his mom finally comes to her senses and starts working hard to be a good mother.