Giving you an idea would be defeating the purpose of taking the creative writing class wouldn't it?
I will give you a site that may help you with forming an idea, its made for a feature length screenplay, but it will help break a character down for you...
http://www.screenplaymastery.com/structure.htm
The site is somewhat elementary, but it may help you. Just make sure you break down your acts correctly within the 20 pages. Not really sure why it HAS to be 20 pages, thats to much for a short and obviously to short for a feature. I would think it would be more of an interesting read if kept under 10-12 page...but thats just me...
Since its 20 pages use your pages wisely to create suspense and an ultimate payoff. You don't want any downtime within the story since its so short.
Think bank robbery, man/woman and suicide, etc....those may be cliche, but you get the hint...Or you could do a short type of 'Magnolia' type story. Use 3 situations that lead them all to one moment....
Just my thoughts....
Creative Juices
