Jem breaks "the remaining code of their childhood." How does he do this and is he right?

  Jem decides to be responsible and tell Atticus that Dill had run away and was caught hiding under Scout's bed. Jem is certainly growing up. He realizes that it is impractical to hide Dill. There would be people looking for him. Dill trusts that his father will best know how to handle the situation.