One night, after lights out, one of my mates decided to sing "10 Green bottles", except that he thought it would be funnier if he started somewhere around 50.
By the time he got down to the mid-20s, one of the other guys in the tent had had enough and told him "That's it! Enough. There is one bottle left, and then the song is OVER".
Our singer responded with:
"One green bottle, hanging on the wall
One green bottle, hanging on the wall
And if one green bottle should be accidentally ADDED
There'd be two green bottles, hanging on the wall
Two green bottles, hanging on the wall...."
Etc
I suddenly feel less distressed about missing parent teacher night.