Choose two nouns and a verb out of a dictionary, flash card set or from your own mind. Tell children to write a short story including those three words. Help them think about the various possibilities for a story. The nouns could be familiar characters, animals or inanimate objects, and either one or both of them could perform the verb. That action could have a variety of results, or the action could happen at the end to solve the characters' main problem.
Put children in pairs. Tell each pair to imagine a place and describe it to one another, then write down a description in one or two sentences. Have each student create one person or character to inhabit the described setting, then tell the pairs to write a sentence each about their characters. Finally, tell each pair to create trouble for or between the characters, and describe it briefly. Assign each child to finish the narrative with a paragraph-long story about how the characters resolved the trouble.
Instruct students to imagine themselves as someone else. Students may imagine themselves at a different age or in a certain job, a new geographical setting or a different period in history. Ask them to think about what would be different in their experiences, daily routines and relationships. Have them write a short story about what life would be like in the situation they have imagined.
Provide a variety of toys that suggest characters, props and settings such as dolls, picture blocks, play sets, action figures and stuffed animals. Instruct students to pick a few toys and, working individually or together, to make up a story using those characters. Once the children have had some time to play with the toys and develop pretend scenarios, call them back to their desks and instruct them to write their stories down in a paragraph or two.