Summer brings a whole fresh round of distractions to the classroom. The man cutting the grass outside the window and the afternoon sun promising picnics, beaches and holiday fun take over from Wayne being sick in the corner, perhaps, or Tracey using the art scissors to make ad hoc alterations to Charlene's French plait?
But for real grade 1 disruption there's nothing to beat a wasp. Experienced teachers are only too aware that the first hint of its menacing buzz will have the lesson plan flying out of the window - unlike the uninvited insect.
Some teachers can cope. They remain cool as Wayne is stung by the biggest wasp in the land. "Stop that ridiculous noise," they hiss, as Wayne faints and the class sit tight, fearing the consequences of making a beeline for the door more than they fear becoming the wasp's next victim.
But for most of us, a wasp spells chaos. There will be squeals and screams. Boys will itch to jump on desks with rolled up worksheets. When it lands in Charlene's hair there will be a clamour of advice, ranging from "Look out Charlene" to Tracey's suspiciously solicitous "Let me cut it out" as she reaches for the scissors.
You are supposed to be in charge, and the only practical solution is to abandon the lesson and organise a hunting party. Corralling the timid and the hysterical into one corner, you can select one or two from the army of volunteer bounty-hunters and set them to it.
Under no circumstances attempt to deal the dreadful blow yourself - that way lies humiliation. A supervisory role allows you to criticise Wayne's technique and thereby maintain some semblance of control. Just hope no-one decides to pop their head around the door at this point, to witness Wayne and Tracey climbing over the furniture while you cower in the corner with the rest of the class.
Once the deed is done and the striped intruder has been reduced to a sticky smear on someone's desk - "Ohhh I'm not sitting there" - you can return to the lesson.
"Now then," you say in your brisk, that's-enough-nonsense voice.
"We were talking about reincarnation. Can you explain what that means Charlene?"