TUESDAY Two consecutive lessons, two brothers, the same distracting chattiness. I tell the older one he is worse than the younger; next lesson I tell the younger one the reverse. At break, having swapped notes, they ask what I meant. “Oh, you’re each worse than the other,” I say with a grin. “Or do I mean ‘better’?” They get the joke and promise to concentrate in future. The concept of “reverse psychology” seems to be becoming the week’s trend.

WEDNESDAY A girl in my Year 9 class asks to be moved because the boy next to her has been scribbling on her book. I am astonished, as the boy is hard-working and keen. I make inquiries. To the girl’s disgust, he points out that she probably wants to sit next to her friend. I offer her a place at an empty table near me. She declines and I hear no more complaints - but she suddenly starts asking and answering a lot more questions.

THURSDAY Year 10‘s turn to hear an impassioned assembly on care and respect in the school community from one of our deputy heads. It is powerful, heartfelt and true. Staff resolve to reinforce the message in the classrooms; the Year 10s seem to take it as a signal to behave worse than usual. Sometimes we wish reverse psychology wouldn’t work.

FRIDAY The same Year 10 class I taught on Monday reappears, with the same silly behaviour. I tell one of the boys to stop messing about. The other digs him in the ribs and mutters: “Don’t worry, you wouldn’t get caned for it.” “That’s true,” I say. “In my day such behaviour would have got you expelled before the end of Year 9.” Grins disappear and behaviour improves, for the time being at least. It’s nice to get in your punch line, even after a five-day delay.

Colin Padgett is head of department in an Essex comprehensive