I found that Disney's Pixar's movie, "UP" is an excellent tool for introducing the types of conflict to middle schoolers. While my students watch a short clip from the movie, they complete this graphic organizer. I think you could use multiple clips from the movie, my favorite is the scene where Mr. Fredrickson is alone for the first time, up until the house lifts off the ground. I like this scene because it shows the students a person vs. nature conflict that isn't weather (old age, bad hearing ect.) They then use this as a reference when they are finding examples of conflict in their own novels.