Before I help in class, I have to get my youngest son to nursery. Normally, this involves packing him in a friend’s car and rushing to school with the stragglers and latecomers. This morning, his friend is ill, and I drive to nursery myself. But when I return to school, the back gate in the new security fence is locked.

Until the new fence sprang up, a locked gate posed no problems. The previous fence consisted of a large number of gaps held together with a small amount of wood. But this fence is tall. Metal. It could stop a herd of rampaging wildebeest, let alone a tardy father. I have to go the long way round.

Not that it’s such a long way. It’s a long way like the wait for the red man to turn green is a long wait. Incidentally, since becoming a dad, I always wait, even if (a) I am alone and (b) the nearest car is a quarter of a mile away. Inevitably the faraway car reaches the crossing just as the lights turn red. The driver glares at me, and I have to fake a limp to show there was no way I could cross without assistance.

When I get to the front door, there’s a buzzer and an intercom. What to say? “It’s me!” Too vague. “It’s Michael Cook.” Too formal. “It’s Poppy’s dad, coming to help in class six.” Too much information.I swear I can see someone inside, but there is no reply to my buzz. So I become Mr Grumpy, cursing society’s slide towards over-protection, blaming everything from bark chippings under climbing frames to silicon-chipped identity cards.

(The poster for the new adaptation of Pride and Prejudice warns us:

“Contains very mild innuendo”.) This is a school. I am a parent. No, better than that, I am a parent-helper. Let me in! But I have been in the reverse situation. I have been photocopying in the lobby when the bell has rung. I have wondered if I should open up to a stranger. And yes, I see a red-faced, sweating crank reflected in the door. Me, looking like a Gruffalo. Let me in? Not by the hair of my chinny-chin-chin... When I do get inside, I have to explain my lateness to Poppy. As she’s a sensitive soul, I can’t talk about the fence or the door. I don’t want her to think the world is a dangerous place. Already, she is scared of burglars, even though we have never been burgled and, as my kids keep reminding me, the miscreants would have nothing decent to steal anyway.

Burglars wouldn’t want our lousy PlayStation 1 when there are PlayStation 2s to be pinched. We’ll be OK, I say. Be grateful we’re not like the friend of a friend of a friend who is reportedly the richest man in the county. At least he is protected. Apparently,the richest man in the county made all his money fromI? Yes. Security fencing.

Michael Cook is a freelance copywriter and a parent helper at Ernehale infants school, Arnold, Nottingham, which his children, Alfie and Poppy, attend