Write on the whiteboard/blackboard this line:
“Why haven’t you done your homework?”
Then tell students you want them to write the most bizarre, ludicrous, creative explanation they can think of. Give an example for those who may have trouble starting, such as ‘I was in my room trying to do my homework when a beam of light came through my window and transported me to an alien spaceship…’ Cater the example to the age group, for a younger group you might simply say, ‘I was abducted by aliens’. Younger students may only have to write one sentence, but older students should be given a minimum, such as three paragraphs.
This is a great writing exercise for reluctant writers as it gives them the opportunity to write something silly and fun. Because it is open-ended, eager writers have the opportunity to write an entire story if they wish, while less confident writers can simply write the minimum specified by the teacher.