On the first day of school, Miss Caroline tries to give Walter Cunningham Jr. a quarter for lunch, telling him to pay her back the next day. Scout tries to explain to Miss Caroline that Walter doesn't have the money to pay her back. Scout doesn't consider the fact that Miss Caroline doesn't know all of the social and cultural (unwritten) rules of Maycomb. In Chapter 3, Scout realizes this after talking with Atticus:
Atticus said I had learned many things today, and Miss Caroline had learned several things herself. She had learned not to hand something to a Cunningham, for one thing, but if Walter and I had put ourselves in her shoes we’d have seen it was an honest mistake on her part. We could not expect her to learn all Maycomb’s ways in one day, and we could not hold her responsible when she knew no better.
This is one of the most important lessons in the book. Scout learns to consider Miss Caroline's point of view. The lesson is to consider the perspectives of other people, no matter what the situation is.
Following school, Walter arrives to have dinner at the Finches' home after Jem's invitation. Scout makes fun of the way Walter eats and Calpurnia reprimands her for it. Calpurnia tells Scout that she should treat Walter with respect after Scout remarks that Walter is "just a Cunningham." Scout at least begins to learn that she shouldn't be condescending to others simply based on their social or economic status.