How are readers and miss caroline similar in their understanding of maycomb society at this point in the novel? how does harper lee use the character of miss caroline to introduce readers to what everyone else in maycomb already ""knows""?

The readers as well as Miss Caroline hadn't been introduced properly to the Cunninghams before the school scene in Chapter 2. So, they are all unfamiliar about the Cunninghams' sense of pride.

Harper Lee used the character of Miss Caroline to introduce the Cunningham family to the readers and also to clearly understand the situation about this family.

Explanation:

In Harper Lee's "To Kill A  Mockingbird", the character of the Cunninghams were not introduced until Chapter 2. There, Walter Cunningham is seen going to school without bringing lunch. When Miss Caroline offered to buy him lunch, Scott sad that they are "the Cunninghams" as if that will make Miss Caroline understand anything. But quite contrarily, she has no idea what the connotation means. That's when Scott began to explain to her about the Cunninghams - "never took anything they can’t pay back—no church baskets and no scrip  stamps. They never took anything off of anybody, they get along on what they have.  They don’t have much, but they get along on it". This clearly sums up and also give a detailed summation of the family.

The author Harper Lee used the character of Miss Caroline in introducing the Cunningham pride and also giving us the chance to know more about them. It enables us to know better about the Cunninghams as a family unit.