Imaginative Writing workshop
This workshop from Seven Stories can be used to start a imaginative writing session with your class. Think of an object, concentrate on a place, describe how it feels and how it makes you feel and the next thing you know your story has begun.

The Robert Westall archive film is a good starting point for this workshop. You can download the teachers notes to accompany this workshop below.
Getting started
Imagined place
Recording one
Recording two
20 years on
Westall film