1. Choosing either an existing character or an entirely new story, write a setting that involves people gathering over something that they are passionate about (political fundraiser, church, art gallery opening, a new business, something that people work on to enact change or action) and have something intervene or enter the scene that is from the world outside of it. It can create a positive or negative version of tension but it should change "the temperature" of the room in some way.
2. Have your character/s (old or new) respond to an object (my class example was a home being delivered in halves--a prefab home). Does such a dwelling resonate with your characters? Do they like modern art? How about a really funky Jeni's ice cream type flavor? Anything that you can place them in a scene and have them work with or against.