Lions and tigers and bears, oh my! Or perhaps something even scarier. It's all up to your students how far they delve into the frightening depths of a situation gone wrong.
You want your students to create and then describe/narrate their own storyline for a HORROR film. Medium-sized groups are probably best for this. Give them ample time to prepare, and then have them share it with the class.
Potential Elements:
A man wearing a mask
A monster that lives in a lake
Giant spiders
Snakes
Rats
A phone call with a deep, scary voice
Vampires
Zombies
Ghosts
Werewolves
Flesh eating something or other
In a school
In the park
In the mountains
At home
In the woods
In an office building after hours
In a cemetery