S.E. Hinton weaves together a couple of pretty compatible genres to create the overall effect of The Outsiders. After the initial introductions to the characters and the basic conflicts, we find ourselves on a wild ride full of fights, rumbles, shootouts, and the flashing bulbs of newspaper cameras.
Everything is a matter of life or death, triumph or failure. In this chaos, Pony begins to "come of age" or become more prepared for life as an independent person. It's safe to say that Pony does this the hard way and not, for the most part, by choice—though the choices he's forced to make sure do matter.
This is a super-hard lesson, but ultimately knowing that our choices matter can be empowering. By the end of the novel, Pony's learned that he can have more control over his life, starting with how he interacts with his brothers at home and with the choices he makes out in the world.
As you can see, there's lots of drama in the Curtis home. Pony's increasing understanding of his brothers—how they feel, what motivates their actions, what they hide inside themselves—is part of his path toward maturity and self-sufficiency.