In Chapter 2, why does Walter Cunningham's jaw muscle twitch when his teacher asks him if he forgot his lunch? What other evidence from Chapters 2 and 3 offers insight into the social and economic differences in Maycomb?

Walter Cunningham's jaw muscle twitches because he is ashamed and self conscious about his low income. The teacher is new to Maycomb and is unaware of this economic difference that is present in Maycomb.

Explanation:

Scout explains to the teacher how the society works and why certain last names are based of off their economic level. This is also shown in the way the children act towards each other.