They are the one-day wonders of the school world: the supply teachers who make such a distinctive impression that they are never invited back.
Teachers have been posting recollections on The TES online staffroom of agency staff who only lasted a single day in their schools because of laziness, inappropriate behaviour or eccentricity.
One primary teacher described how a supply teacher had captivated a Year 2 class by showing them a shoe-box and inviting them to guess what was inside.
The lesson was a success, producing "lots of lovely, imaginative ideas and great language" from the children. But it ended on a macabre note when the supply teacher opened the box to reveal a dead squirrel she had run over while driving to the school that morning.
More common misdemeanours by supply staff included chatting to their friends on mobile phones during lessons, picking their noses in front of their classes,knitting, and bribing pupils to behave with money, cough sweets or cigarettes.
Some showed an almost touching disregard for their pupils' abilities and interests. One bravely attempted to teach quantum physics to a class of five year-olds in a primary school.
Another spent the day singing Monty Python songs and repeating the comedy group's sketches. "The pupils wondered what he was on," a full-time teacher said.
A more imaginative teaching method was demonstrated by a supply teacher who worked with Y6 classes in a primary school. He made all the pupils sit round the desk and told them that that if they concentrated for an hour without making a sound he would levitate.
"There was silence for an hour, but of course he couldn't rise to the ceiling and made the excuse that the air wasn't right," teacher "marshallb"
"He repeated the lesson with three classes he had that day. It worked in all classes - absolute silence and no preparation or marking. I never saw him again."