After reading the novel and watching the movie I noticed some differences, I'll start with Ponyboy, in the novel pony boy is slapped by his brother, but in the movie, he is pushed, I think the actors couldn't fake the slap or wanted to harm the actors, this difference wasn't very good it took away some of the drama. Another difference is that in the movie it ends shortly after Dally's death and in the novel a lot happens after that; this was a very bad change to the film, like pony boy breaking the glass was definitely a point that made the novel more enjoyable. One similarity in the book and novel is that in both he cuts his hair and dyes it blonde.
Johnny also had some differences in the novel and in the film in the novel Johnny is jumped and has a large scar across his cheek; in the movie it isn't very noticeable. This difference is good because it would attract a lot of attention instead of the viewer focusing on other things. In the movie and novel he has his jean jacket that he wears throughout much of the movie.
There is also Dally still has his outlaw look of his troublemaker self, this was very important the book and movie. Also in the book he robs a drugstore, but in the movie he takes a book and rips it up then scares the cashier then runs away, this was an okay change, it did not make a lot of difference, maybe the director thought it would stir up some more action.
Some events also had their differences, in one of the church scenes; Ponyboy and Johnny try to catch a rabbit in the film version, in the novel version there was no bunny catching. The movie might have needed something more,...