It's hard to sneeze in front of a classrroom full of teenagers.
You feel one building, and you excuse yourself, say, 'sorry, I'm going to sneeze.'
Then you realise 15 teenagers are gazing at you expectantly and your sneeze gets performance anxiety and retreats to tingle stingingly somewhere deep in your sinuses, leaving behind a vengeful I'll be back!
That was at 10.45, and it just got me at 5.30.
**Google image has some GREAT sneeze images, but I found this post about stopping a sneeze that was informative and somehow entertaining.