Love this writing prompt -- fix the worst book or movie that you know.
This is a great list!! Could be good for most ages! SmallWorld: 100 Not-Boring Writing Prompts for Middle- and High Schoolers
Write a story about this picture. Or use as a cause & effect prompt-- half the class writes a paragraph about about what caused this and the other half writes a paragraph or two about what the effects of this picture are. Then randomly match one of each together and read out loud. Kids love it!
descriptive details; setting #692 secret lair [This one is from a set of 300 Common Core aligned writing prompts that I put together.]