The quotes in the above post can be found in Chapter 15 and Chapter 24 of the novel.
I'm not sure that I would call Scout particularly courageous in To Kill a Mockingbird, but some of her actions would be considered courageous if not for her reasons for initiating them. The fact that Scout is willing to duke it out with any boy who rubs her the wrong way could be called brave, but it is Scout's temper who pushes her into these scrapes--not a sense of honor. When Scout intercedes between Atticus and the lynch mob, it would be considered a particularly brave act--if Scout had understood what was going on between the men. Scout had no idea that Tom's and Atticus's lives were in jeopardy: She simply began making innocent conversation after recognizing Mr. Cunningham. Of course, her temper led her to take on yet another male--this time an adult one--when she defended Jem when one of the lynch mob grabbed him by the collar.
I kicked the man swiftly. Barefooted, I was surprised to see him fall back in real pain. I intended to kick his shin, but aimed too high.
Perhaps Scout's most courageous moment came at the Missionary Circle tea when she managed to hold her tongue after Miss Stephanie made fun of her. She listened to Mrs. Merriweather's hypocritical diatribe silently, and then watched her Aunt Alexandra and Miss Maudie recover from the news of Tom's death and return to serving refreshments, as if nothing had happened. Although Scout hated the idea of becoming a lady,
... if Aunty could be a lady at a time like this, so could I.