Colin had spent the first 20 minutes of story time punctuating the tale of The Iron Man with his sniffing. He had treated his 10-year-old peers to the whole range of olfactory inhalations from the short, sharp sniff to the protracted, bubbly snort and it was driving me mad. Colin loved the attention he was getting.

When I could stand it no longer I dismissed him from the classroom, recalling him when I had finished reading.

Left alone at the end of the day I had a feeling of nervous foreboding. Colin’s father had a reputation. He was never seen at open evenings, sports days or parents’ consultations, but he made his presence felt in a different way. With bovine pugnacity he hunted down any member of staff that he felt had infringed the rights of his son. Colin had the right to wear an earring if he wanted to, he had the right to have chocolate and cakes in his lunch box, he had the right to bring a mobile phone into school. And if he was told off for any of these rule contraventions then Colin was being picked on again and Mr X was having none of it.

I tried to concentrate on my marking, but I was drawn to the window that looked out to the front entrance of the school. Sure enough I saw Mr X, stomach straining against tight football shirt, bowling along. I couldn’t face the scene so I gathered my bags and made my getaway out of the back fire exit. A strategy not to be sniffed at if you’d ever met the infamous Mr X.

The writer is a primary supply teacher working in Kent.