Consider two or three characters in "To Kill a Mockingbird" and discuss the kind of courage each possesses.
One of the most obvious examples is Atticus. He takes on Tom Robinson's case, even though he knew that it wouldn't win in court. He took it because it was the right thing to do, and it would teach his children a valuable lesson in the value of human life, no matter what station one comes from. This requires a great amount of courage, because he knew that taking the case would draw a lot of mockery, violence, hatred, and ill-feelings from people in the town, putting him and his family at danger. However, he did the right thing despite the possible risks involved.
Another character that shows courage is Mrs. Dubose. Although she's a feisty and mean character, she decides to overcome her morphine addiction. She gets a bit further each day, and is able to die free from her addiction to the insidious painkiller. For this, Atticus calls her "a lady," because she showed grit and courage despite the very difficult and potentially impossible road ahead of her. But, she managed it, and stuck it out, even when it was hard.
Those are just two characters; consider Tom, telling the truth in court despite a possible sentencing, Boo Radley, emerging from his house after years of isolation to fight off an unknown attacker, Tom's wife, walking to work every day despite threats from Bob Ewell, and many others in the book that stood up for what was right. I hope that those thoughts help; good luck!