We were having such a serious problem with litter at our school that we decided to address it in an assembly. I first had the idea when I saw one of our teachers showing a group of pupils around the building, scraping gum off the walls as she did so.

I wasn’t horrified that pupils were chewing gum - that will always happen. It was the fact that pupils were so lazy that they felt they had to stick their finished gum to a wall, under a chair or a table. After all, if you’ve been caught chewing gum there are many other ways to get rid of it.

The final straw came on the Thursday before we broke up for the holidays, when I looked back at the corridor as I left my office and the whole place was strewn with litter. If I’d had a camera at that point I would have taken a photo to show how revolting it was. Sweet wrappers, cling film and crumbs, papers and all kinds of things lay thrown across the floor.

I wanted to widen pupils’ awareness of litter beyond school too. According to the Environment Agency, the amount of rubbish dropped on our streets has increased by 500 per cent since the early Sixties. Dropped food and takeaway litter has helped swell the rat population to 60 million. You could illustrate this with some of the public information films and advertising campaigns available from www.encams.orgcampaigns.

Stress to pupils that, while they may forget about the rubbish they drop as soon as it falls to the floor, the environment doesn’t. As the wind blows their rubbish out of sight, animals fall over it, eat it or get tangled up in it - small animals have suffocated to death by getting tangled in sandwich wrappers, dogs have had their tongues injured and even cut off as they go to lick broken tin cans, birds and ducks get their feet and wings trapped in bags and many have died from trying to eat sweet and chocolate wrappers.

And just because some rubbish is biodegradable, for example banana skins, it doesn’t necessarily make it safe. Ask your audience how long they think it takes different bits of rubbish to biodegrade, perhaps by using a PowerPoint presentation:

Now they’re thinking about it, what are they going to do about it? Repeat the “reduce, re-use, recycle” mantra. Reduce the amount of the earth’s resources that we use. Can we buy products that have less packaging? Can we pack more into the plastic bags we take from the supermarkets? Do you sometimes take a bag from the checkout when you don’t really need one? Reuse: Don’t just bin your rubbish without thinking. Could you refill that water bottle? Could someone else make use of whatever it was you were about to bin? Recycle: Many of us have recycling facilities at home and I made the pupils laugh by telling them about my husband, who continually moans as I shout at him for putting the wrong thing in the wrong box. Environmental experts claim that the landfill sites, the places where rubbish is dumped and left to biodegrade, will be full soon, and recycling stops the landfill sites being filled as quickly.

This week, I concluded, think about the school and wider environment around you. Clear your plates properly at lunchtime, don’t drop rubbish on the floor and don’t bring gum to school.

With pupils more aware of the consequences, I hope to see a tidier picture at the end of this term.

Hannah Nemko is assistant headteacher at Yavneh College in Borehamwood.