Favouritism cannot exist in a well run classroom, and sometimes teaching is a frustrating job for the most unlikely reasons.

I am sitting in the staffroom at the end of class. It's been a tough morning - an hour in the gridlocked traffic, a sick child at home, sinister plumbing problems and the usual school irritations. The mood is grim. Alex, in sixth year, has been "behaving immaturely" and we have exchanged words. My head is now frostily bent towards some notes. The door is open. I can sense someone trying to move into my line of vision but I don't look up. The body moves back a step, hovering there to the point where it is difficult to ignore it. Fatally, I look up. It is Alex and he winks at me. It's the "loosen up, get a life lady and I'm a lovable rogue, really" sort of wink.

I fix him with my glassiest stare but he remains there smiling, not cheekily - just pleasantly disarming. Then it's no good and my carefully held composure collapses into a natural warm grin. For no logical reason, my morning has brightened up immeasurably. Then he's off on his way. I've always been a sucker for lovable rogues. Later we meet in the corridor and I wink discreetly back at him and from that moment we are on a wavelength of sorts. A normal workplace situation, surely?

But later in the staffroom we get to discussing the need to maintain impartiality in the classroom. As teachers we are encouraged to be friendly but not familiar, kind yet firm when the need arises. But as in life, there are those with whom we immediately feel a common bond and others that we understand less easily. Like ordinary people working in the real world, we are drawn to have a giggle or a softer word with some and, like other people, we find ourselves less enamoured of others.

This, of course, is mostly as it should be, as young people are more comfortable with teachers who maintain a professional distance. But the dynamics of classroom interaction require us to behave in a false way, sometimes totally against the grain of our natural personality. (We all know about teachers who go into class and think they can get down to the students' level - a recipe for disaster).

As it is, Alex will never know quite how much his wink and disarming smile cheered me up that morning. He won't know that now I have to work twice as hard at being cross with him when the need arises. He wont know that he has well and truly entered my gallery of lovable rogues. He doesn't need to know and it would be favouritism to tell him.