E.g Each paragraph can focus on a place in maycomb (School, home, courthouse) and that can show an Idea, the idea could be Prejudice.

School: Class Prejudice

“Whole school’s full of ‘em. They come first day every year and then leave. The truant lady gets ’em here ‘cause she threatens ’em with the sheriff, but she’s give up tryin‘ to hold ’em. She reckons she’s carried out the law just gettin‘ their names on the roll and runnin’ ‘em here the first day. You’re supposed to mark ’em absent the rest of the year”  

“There’s four kinds of folks in the world. There’s the ordinary kind, like us and the neighbours, there’s the kind like the Cunningham’s out in the woods, the kind like the Ewell’s down at the dump, and the Negroes.”

“But Miss he’s a Cunnigham”

“Because— he—is—trash, that’s why you can’t play with him. I’ll not have you around him, picking up his habits and learning Lord-knows-what.”

“The thing is, you can scrub Walter Cunningham till he shines, you can put him in shoes and a new suit, but he’ll never be like Jem. Besides, there’s a drinking streak in that family a mile wide. Finch women aren’t interested in that sort of people.”

“He ain’t company, Cal, he’s just a Cunningham-”

Courthouse: Racism

“in our courts, when it’s a white man’s word against a black man’s, the white man always wins.”              

“Well, Dill, after all he’s just a Negro”

“To Maycomb, Tom’s death was typical. Typical of a nigger to cut and run. Typical of a nigger’s mentality to have no plan, no thought for the future, just run blind first chance he saw […] Nigger always comes out in ’em.”

“but around here once you have a drop of Negro
blood, that makes you all black.”

“They don’t belong anywhere. Colored folks won’t have ‘em because they’re half white; white folks won’t have ’em cause they’re colored, so they’re just in-betweens, don’t belong anywhere. “

“Mr. Dolphus Raymond was an evil man”

I liked his smell: it was of leather, horses,
cottonseed. He wore the only English riding boots I had ever seen.

Home: Sexism

“In the first place you never stopped to give me a chance to tell you my side of it – you just lit right into me.”  

“For one thing, Miss Maudie can’t serve on a jury because she’s a woman.”  

“I don’t want Dill waitin’ on me” “I’d rather wait on him”  

“What are you doing in those overalls? You should be in a dress and camisole, young lady! You’ll grow up waiting on tables if somebody doesn’t change your ways”

“I could not possibly hope to be a lady if I wore breeches; when I said I could do nothing in a dress, she said I wasn’t supposed to be doing things that required pants.” (Not said out-loud but is thought by Scout)