The Question and Answer section for The Outsiders is a great resource to ask questions, find answers, and discuss the novel.
The children gathered together because a fire was burning in the church.
There was a crowd at the front of the church, mostly little kids, and I wondered how they'd gotten there so quickly. I tapped the nearest grownup. "What's going on?"
Do you mean like the Socs and Greasers?
The building was on fire and there were school children in it. Pony's clothes were on fire so he hit Pony to put the fire out. We know that Ponyboy was unconscious because Jerry Wood related the facts to Ponyboy.