If the story is supposed to be short, satire, and for children, I think writing a fable or fantasy might be your best bet. Maybe try writing about something like superheroes, wizards and witches, or something with animals. Try and make the conflict as obvious as possible so that the children would be able to pick up on it easily; if there's a villain, make it clear who it is and what their intentions are. These are all ideas, not requirements, and I highly suggest you come up with something on your own.
When you got an award and not just your friends would clap for you, but the whole assembly hall. And when you went on school trips, you would always have fun and just mess around with them.
