No Ball Games

There are two kids, standing in the middle of a playground. Between them on the ground is a ball.
Other children are sitting or standing in groups around the perimeter of the playground, watching the two.
There is no teacher.
No one is moving or talking.

One of the children in the middle of the playground is wearing a badge which reads 'prefect'. You can tell he has made it himself. He might have used a computer and a printer, because it looks like it might be official, but it isn't certain. Regardless of this, the boy with the Prefect badge is standing tall, staring stiffly, one hip out, his head lolling gently with an assurance which is oddly echoed by half of the children around the edge of the playground.

There is no teacher.

The Prefect's opposite number is bristling. He is shorter, more strongly built, maybe a little older. He has a badge, too. The lettering is pretty small, but the background is a bright green and stands out. The badge says 'Ball Monitor'. Again, there is the suggestion that he might have made it at home. The Ball Monitor is weaving gently, shifting his weight from foot to foot ever so slightly, glowering at the Prefect. Behind him, children leaning against the wall stare darkly across the grey tarmac at their opponents.

Suddenly the two sides charge at each other and the children are fighting, biting, kicking, punching, tearing, swearing, bleeding and dying.
There is no teacher.

This isn't a very nice story.
Read it again if you like, because I'm going to talk about what I didn't say.

I never said where the playground is.
I never said who or what the children are.
I didn't say just how big the ball is in real life, or what happened to it because of the fighting.

I did say that there was no teacher. I have weighed up a fair bit of the available evidence and I have come to the conclusion that there never was a teacher. That's because the big thing I left out was this:

The story does not take place at a school.