After Scout begs Atticus not to make her return to school, what advice does he give her for getting along with people?

Scout doesn't want to go to school because she and the teacher cannot get along.  Scout is proud that Atticus has taught her to read, but Miss Caroline Fisher is not impressed and tells Scout, "Your father doesn't know how to teach" (22).  Ms. Fisher continues to show her ignorance of the southern town, Maycomb by insulting both Walter Cunningham and Burris Ewell.  When Scout tries to explain to the her the situation with Walter, Scout is called to the front of the class, and Ms. Fisher slaps her hand. 

In Chapter 3, not Chapter 1, Scout begs Atticus not to send her back to school.  Atticus uses this moment to introduce one of the motifs of the novel.  He tells Scout, "You never really understand a person until you walk around in their skin," indicating to Scout to consider things from the other person's point of view.  He also tells her that sometimes it is necessary to bend the law, but she must obey the law.  He then instructs her that it is sometimes better to ignore things.  He uses the example of Jem in the tree house.  He tells Scout that if she would just ignore Jem, he would come out.

At the end of the Chapter 3, Atticus and Scout reach the compromise that if she will go to school, they will continue to read at night.  He also instructs her not to tell the teacher, reinforcing two of the lessons of this chapter:  sometimes you need to bend the rules, and sometimes you need to ignore things.