It was the unhappy consequence of hermaphroditism in the giant land snails in the tank in the art department. Unhappy for us, though probably less so for the two snails involved. They did what snails do everywhere. Despite existing only on an endless diet of cucumber, they found the strength from somewhere to make babies.

Our snails were transformed. Once the inspiration for interesting sketch work, they were now a baby farm. This was not good news.

What do you do when you face an endless supply of snails? Our first heartless but necessary response was to insist on separate tanks, which teachers reading this in France may feel was a bit of a waste. Perhaps they arrange these things differently there, but for the teacher here, their new-found relationship was a problem. Our next heartless move was to place the babies outside in a bag in the frost, for nature to take its course.

But a trespasser found the bag and the word got out into the community about what the school had done. We were threatened with the press. The spectre of animal cruelty came to sit on our doorstep. Caretakers refused to move them for fear of implication in a heartless crime.

But it would have been a slow news day indeed that would have placed “Dead Snail Baby Horror!” on the front page. So far, we appear to have weathered this particular storm.

Leaving aside modern techniques for the dispatching of lobsters, which involves putting them in the deep freeze, how cruel was this? Should we have fed them to the birds instead? Perhaps that was the answer. The poor beasts could have lived forever on the vegetation ripped from burgers and thrown on the floor. And this would have certainly provided a fine illustration of a food chain as snails, feeding on gherkins and squashed iceberg lettuce, were snatched by hungry thrushes, only to be shot down and eaten by cruel burger-eating German hunters on their migration route to the south.

What picture of nature do we wish to promote anyway? Bunnies and smiley meerkats? Or the vicious nature of predatory behaviour which, of course, involves ourselves? In this case, is it thus acceptable to sit around and watch the school iguana eat live crickets? And if so, why not feed kittens to the school python? Do we have a responsibility to all animals? Or just the pretty ones?

Was our snail issue really cruelty to animals? Or merely sentimentality? I know that cruelty to animals leads to cruelty to other things. And we need to encourage responsible behaviour, for there is a price to be paid for any neglect. I think schools and animals should be kept as far apart as possible. You might say it is impossible, given that Year 9 can act like rats, but having animals in school is an unwanted complication.

It remains a truth universally acknowledged that the thrill of shoving a locust down a girl’s jumper never leaves an adolescent boy. Indeed, you might think that this is the sole reason locusts evolved.

You will find the goldfish floating upside down in water with an odd tinge, the dissected frog will inevitably end up in someone’s hair and the guinea pig will be forgotten over the holidays. But then a greater power decides that enough is enough. A curse and a pestilence will be upon you if you take matters into your own hands.

So that guinea pig smell never quite leaves the classroom. Then, suddenly, there are the horses on the playing fields, leaving their mark in the penalty area. Flies will crawl from behind old radiators.

Feral cats move in around the back of the school and you learn quickly that they should never be approached. They snarl and spit like the girls in Year 10, though, of course, they are less vicious or irrationally vindictive. Recently, the head lost flesh when trying to move away from the stairs over in technology. I think she said it was a cat, but you never can tell.

There will be the birds in the dining hall, the occasional cockroach in the kitchen, the slavering dog belonging to the local drug dealer, high on free samples, chasing boys with pasties. And nothing will ever match the chaos caused by a single wasp in a maths lesson, where rulers flash inadequately like sabres. And you will know without doubt that the Animal Kingdom is seeking revenge after years of abuse.

No, it is best if animals are kept out of schools completely.

But I fear I am a lone voice, for children are always drawn to animals, though not necessarily with knowledge.

Some years ago, my form class was adamant that they had found a dead kangaroo. I expressed some surprise, for Swansea is not generally well known for its marsupials. Claire said she would bring it in for me to see. The next day, she arrived with a shoebox. I lifted the lid. It contained one small but dead squirrel.

Geoff Brookes, Deputy head, Cefn Hengoed School, Swansea.