classroom, wasp in the

An ultra-urgent version of "dog in the playground" was "wasp in the classroom".
As the game was more urgent, you didn't have time to shout "wasp in the classroom". You'd just shoud "Wasp!", and the entire class would jump to their feet, waving rulers around without any real aim, stand on their desks, throw books at the wasps, and ignore the weak child who would squeal that we were "making it angry". Girls would pull at their hair, convinced that it was in there, or hide under their desks to avoid the books and flailing rulers.
It resembled the Muppets' green room, crossed with Airplane's "Don't Panic - PANIC" scene. Only three things could return calm;

1. By an extreme fluke, the wasp is killed.
2. The wasp flies out of the classroom.
3. The teacher sighs and leaves the room.

Teachers should note, do not bring a can of wasp spray to school for these eventualities. Someone will play hero, the wasp will drown in a concentrated blast of spray before it can even consider being poisoned, somebody will be blinded, the class asthmatic will choke and some girls will cry over the corpse.