At the end of school one afternoon, a parent stopped me in the corridor.
"Our Mark was really upset 'cos he missed school on your afternoon," she said.
"Was he?" I replied.
"Oh, yes. He was really ill, but he screamed and screamed because I wouldn't let him come to school. He loves you - talks about you all the time."
I was flattered. And for a while I felt pretty smug. After all, I reasoned, it's not everyone who can inspire fanatical devotion in just one afternoon a week.
Shortly afterwards, I was manning a stall at the school's Christmas fare.
Along came George, another member of the reception class, accompanied by his mum. While George deliberated how to spend his money, Mum leaned across to me and whispered: "He's terrified of you, you know."
"Yes," she said. "On the days when you take the class, we have a hell of a job getting him into school. He really doesn't like you."
So much for inspiring fanatical devotion. Yet it gave me pause for thought.
I take these kids for a couple of hours a week, and hardly know them. Yet they have strong - and opposing - feelings for me. The thing is, I'm not aware of having treated them differently.
Children are sensitive creatures. It doesn't take much to please or upset them, so it's worth treading carefully. A word of encouragement can go a long way, and a throwaway remark can arouse resentment.
When I was at primary school, back in the Seventies, the headteacher once stopped me in mid-flow at the school disco. Apparently I was dancing out of time, so he gave me a very public crash course. It was 20 years before I could walk on to a dance floor without my stomach churning. I still haven't forgiven him.
On the flip side, I remember one child telling me her favourite teacher was Mrs So-and-So. When I asked her why, she replied, "Because she winks at me in the corridor."
Gary Hayden is a supply teacher in Cheshire
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