Scout and Jem learn a lot in the book. They learned one very important lesson though. That lesson is right from wrong. The children learn right from wrong through many events in the novel, but Miss Maudie teaches them specifically how to respect their others, even though they dont act as they do, and that racism is wrong.
Miss Maudie Taught Jem and Scout how to respect others. When Scout was sitting with the ladies, Miss Stephanie asked Scout what she wanted to be, then made fun of her by saying she wanted to be a lawyer, but Miss Maudie stopped her by just touching her hand, so Scout said "Nome, just a lady" (230). What Miss Maudie is doing is showing Scout that Miss Stephanie is just entertaining the ladies, and isn't making fun of Scout because she wants to be cruel. Miss Maudie also shows the children respect by showing Jem respect by giving him a slice of the big pie. This is teaching them respect by showing them that they will be respect in return, given time.
She also teaches them racism is wrong by teaching them to respect all people, of all colors. She has a helper in this department, who goes by the name of Mr. Dolphus Raymond. He tells the kids that he prefers Negro company because he feels they are more trustworthy than white people. He pretends to act drunk all the time in public. When Scout and Dill find out that the "whiskey" he always has is merely Coca Cola, Scout asks him why he pretends, and he says, "I try to give them a reason, see? It helps folks if they have a reason" (200). Through him, the kids realize that it's wrong to just assume things. Miss Maudie doesn't think Negroes are bad people, she just thinks they are people. She does her best to teach the kids this.
In conclusion, Scout and Jem are learning all the time. They are learning different lessons of life from many different people, like Atticus and Miss DuBose, but the lesson that is most important is telling Right from Wrong, and the person they learn this best from is Miss Maudie.