1. The character I think changes the most throughout the movie, would have to be Todd, he went from being such a shy kid to standing on a table top in front of everyone.
2. Knox didn't change the whole film, he was daring and didn't wanted to be conformed at all the whole movie, he didn't change.
3. He is changed by the boys and who they become, he is still same person not changed too much but those boys changed his perspective on life.
4. Todd feared not being accepted for he was, so he just didn't talk in front of a lot of people till the end, He was a great poet though. Neil feared his father and his approval, he was very good at hiding his emotions and his pain from everyone, including his father, he was a fun person and was great at acting and he loved it. Knox was scared of being like everyone else, he wanted to be his own person not be just another person in the crowd, he wanted to stand out, he was fearless. I believe all of them overcome their fears in some way.