Here are some movies that will show your kids how to disagree, and stand up for a principle (and, in one instance, fail dramatically). It’s a Henry Fonda movie-thon!
Twelve men enter a jury room to determine the guilt or innocence of a teenage boy accused of murder. Initially, only one juror votes not guilty. By the end, the boy is found innocent. Before that happens, there is a lot of tension and conflict. The quintessential movie of how one person can turn things around.
The Ox Bow Incident (NR, probably PG)
Other possibilities include:
The Chocolate Wars, The Breakfast Club, Footloose, The Hunger Games, Hairspray, Aladdin, How to Train Your Dragon, Brave, Mulan, Willy Wonka and the Chocolate Factory (with Gene Wilder), The Karate Kid, To Kill A Mockingbird, Napoleon Dynamite, Friday Night Lights, Dead Poets Society, Boys in the Hood, Mean Girls, Four Feathers, Gandhi, Hero, Lords of Discipline, Men of Honor, Pay It Forward
You can find all kinds of resources including an extensive list of movies that have a point by visiting the resource pages over on my website.