I created a bubble map that worked for all the prompts. This helped my students see how to "stretch" their writing piece. I included narrative, expository, and also persuasive bubble maps along with a blank one for you to write in a reprint with your topic of choice. I also included a few sample writings from a student journal to see how it translated from bubble map to the rough draft.
The bubble maps are great to send home as HW once they were trained. This helped get the ideas flowing and then we would work on the rough drafts in class. The "bubbles" are small so it is a few words rather than sentences because this is part of their brainstorming process where I just needed them to get something to start with. Length or spelling didn't matter to me on the bubble maps, but if that drives you crazy you may want to add lines so you get more than a few words for each bubble.