Jem gets upset that Nathan Radley covered up the knothole where he believes Boo was giving him gifts, now that its covered he feels like he lost a friend. This develops the theme by showing that Jem is starting to understand Boo.
Atticus tells the kids that their snowman that's based off of Mr. Avery wont be such a nice image to him, Mr. Avery. This develops the theme by teaching the kids that things that seem innocent can be hurtful to others
After telling Atticus what a boy called him at school, Atticus tells Scout that people will have their own opinion but if you want to do something you should and ignore what anyone says. This develops the theme by teaching scout that she shouldn't care what others shave to say.
To Be Continued...
The kids think Atticus is old and cant do much other than read a book. When a rabid dog comes to town and Atticus takes the gun and shoots it Jem is speechless. This develops the theme by showing Jem that he shouldn't judge someone right away.
After cutting all of Mrs. Dubose' flowers all off he has to go to her house everyday for a month and read t her. This develops theme by teaching Jem that his actions have consequences.