In chapter 16 of To Kill a Mockingbird, what does Atticus tell Jem and Scout not to do? And what do they do?
Atticus orders Jem and Scout to stay out of town on the first day of the Tom Robinson trial in Harper Lee's To Kill a Mockingbird. And the children obey his directions all morning, watching the crowds go by (and gossiping about most of the peope) before joining Atticus for lunch at home after the selection of the jury. However, with their curiosity peeked, they can't resist the urge to wander to the courthouse to peek inside. After securing a seat in the Negro section upstairs, they witness exactly what Atticus did not want them to see. They see Bob Ewell in all his trashy glory. They hear first-hand the testimony of his daughter Mayella, and then they see Tom Robinson tell his side of the story. It was all too much for Dill, who begins to cry, so Scout leads him outside to cool off under "the fattest live oak and we sat under it." There they learn the secret that Dolphus Raymond has kept from the rest of the town.
It is precisely what Atticus had hoped to keep from his kids: Tales of sexual transgressions and violence; "alcoholic" outcasts and, later, the true explanation from Tom that the jury refuses to accept. They are the only children in attendance, and Atticus knows beforehand what will occur. For Jem and Scout and Dill, it is yet another lesson of the cruelties of the adult world, one in which all three children come to witness so very early in their lives.
The day of the trial has arrived. Atticus has breakfast with his children, Scout and Jem. He has a discussion with them about Southern mobs. They try and understand but they don't. Atticus is concerned about the behavior of the people in the town. The night before the people in the town had gathered at the jail making threats. He tells his children as he prepares to leave to go to the trial:
"Jem, I don't want you and Scout downtown today."(158)
The children, and their fiend Dill, sneak off to the town and to the court house. They try to sneak inside and find seats but the courtroom is full. They have to sit in the section where the black people are allowed to sit.