Working with teenage girls is all too frequently a terrifying experience. I find a policy of don't-go-within-three-yards-of-them works quite well most of the time.

As a teacher you have to use praise alot, though it takes a time to get it down to a fine art as when I praised one of my pupils for working so well they called me a suck-up, but that's another story. I have several stampers for giving my pupils messages of praise, one of which is personalised and reads 'Mr **** says Brilliant' with some stars in the middle. I'm quite pleased with it and my pupils love getting it stamped in their books, even great big year eleven boys.

I was going round stamping some books during my year ten lesson and one of the girls asked if she could stamp her own book. That's fine by me but after I turned my back for a second to check another pupil's work I soon regretted it. When I look at the girl again she's only gone and stamped her nipples, as in on her school shirt, not her actual nipples. At least I assume not, I wasn't about to check. To say I was horrified is an understatement on a par with standing at the South Pole and saying it's a bit chilly.

Imagine now - but not too much - how that must have looked, a girl walking around with 'Mr **** says Brilliant' on her tits.

My own, slightly paranoid, view is that it made it look like I was giving her breasts a seal of approval, kind of like a highly perverted version of a Quality Standard for meat. It wasn't like it was late in the day, there were still three lessons to go, plus break and lunchtimes. She didn't even have a jumper to put on over the top. So numerous other teachers would have seen it, and that's before she gets home. That'll give her mum a fright when she does the laundry. I wouldn't imagine stamper ink comes out too well either.

I'm sticking to using my smiley face stamper from now on.