[eNotes editors are only permitted to answer one question per posting. For additional questions, please post them separately.]
In Harper Lee's To Kill a Mockingbird, when the children play "The Radley Game" in Chapter Four, Scout admires Jem's ability to act like a "born hero."
This description seems to come from Jem's ability to create an amazingly "fleshed out" story of the Radley family, based upon the pieces of gossip they have collected like gems over time, as well as sections that come from Jem's own imagination. (Dill does contribute some details.) The story includes Mrs. Radley—how she looks and how she is treated, as well as the boys Boo gets in trouble with and the judge.
Jem even goes as far as to sneak into the Finch house to take scissors (while Calpurnia isn't looking); Scout admits that when Jem pretends to stab Dill (old Mr. Radley) in the leg:
From where I stood, it looked real.
They would hide everything and stop playing when neighbors, Mr. Radley or Atticus appeared. And they earned puzzled looks from Miss Maudie while she cut her hedge. However, one day they are so caught up in what they are doing that they don't notice Atticus standing to the side, smacking his newspaper against his leg.
When Atticus questions what they are doing, Jem denies everything. Atticus asks if it has anything to do with the Radleys, and Jem denies this also. Atticus' warning that it had better not is very clear. He takes the scissors and returns them to the house.
The boys want to continue their game, but Scout does not because the day they played the tire game and she rolled into the side of the Radley house, she heard laughter coming from inside.
So Jem is a born hero (in Scout's mind) because of the wonderful way he weaves a story and his ability to fill in the gaps where information is missing. Perhaps she is also impressed that Jem keeps his head when Atticus confronts him about their activities.
Scout seemed to enjoy playing the Boo Radley game much less than Jem and Dill. She claims to have preferred playing their previous Tarzan game to their new one. It was probably in part because Scout's roles were not as exciting as Dill's (Mr. Radley) or Jem's (Boo). Scout usually played the part of Mrs. Radley, but she also played other "assorted ladies who entered the script." But the main reason was her trepidation about being so close to Boo. However, Jem assured Scout that he would protect her, and he reminded her that Calpurnia was also home during the day and Atticus was always home at night. Those reassurances, in Scout's mind, made Jem "a born hero."