I was putting up with a lot of disruption from Louisa during science lessons. I had tried everything, but to no avail.
Louisa's mum was a learning support assistant at the school. Nothing happened after she said she would speak to her, so I decided to invite her in to the lesson so she could see at close quarters how her daughter behaved.
The day arrived for her mother to join us. As the lesson progressed, I spotted her frowning at a couple of Louisa's mates sitting two rows behind her daughter, and there was an unusual incident where Louisa yawned ostentatiously and her mum went over to give her a quick cuddle.
At the end of the lesson, mum hung about for a second or two: "Yes, I don't envy you. Louisa is bone idle, only interested in doodling on pieces of paper," she said. "She really is only interested in playing football and I'm not stopping her doing that, because it's the only time I get any peace."
I didn't know what to do next. But it then got embarrassing in the staffroom, especially when I passed the mother and heard my name mentioned. I even once heard her utter: "... and the cheeky mare even got me in once because she couldn't handle her. She won't even let her sit with her mates - she should try not to be so bloody boring."
Last year I spotted Louisa on television - now an 18-year-old - in the role of a sulky youth. I felt proud of my involvement in the perfection of that sneer and vowed to see disaffection in the young in a more positive light from now on.
It's harder to cope with disrespect from colleagues - however, I heard recently that Louisa's mum slipped and broke her ankle while watching her brother play football. Such a shame.
The writer is a science teacher.