They stand to attention at every corner of our school campus. In their bright yellow livery, they are a conspicuous reminder of the prescribed destination of crisp packets, plastic bottles and other relics of the grazing multitude. And they are open at the top, to spare the indolent the effort of lifting a lid.
They may appear light and frivolous. But their bases are concrete, and their hearts grow heavy when those to whose service they are dedicated pass them by. They are our bright new plastic bins, purchased at considerable cost after extensive market research.
Our society is giving up on the idea of making people responsible for their own detritus.
In railway stations and airports the traveller searches in vain for rubbish receptacles. In cinemas you are expected to deposit the gargantuan popcorn container at your feet, and at the World Cup in France the Japanese supporters caused great hilarity by tidying up the area where they were sitting at the end of the match.
Chewing gum is another curse of our times. To add to the age-old problem of chewing in class, the earth will soon be entirely covered in a glutinous layer of sticky pink, the refuse of masticating millions.
At Holy Rood, our school occupies one of the most beautiful campuses anywhere in the country. It nestles on the edge of Duddingston conservation village, against the imposing back drop of Arthur's Seat. Pupils at lunchtime can enjoy the inviting greenery of wide open playing fields.
Derek McQueenie and his team of janitors do their best to keep the school grounds in a tidy condition, and indeed they succeed. But their task is like the labour of Sisyphus, sentenced forever to roll a huge boulder up a slope, only to see it fall back down to the bottom every time.
The local shop is a magnet, attracting our charges in search of their daily intake of additives and colouring. A gastronomic extravaganza of pies, bridies and sausage rolls tantalises them and undermines all the efforts of the School Nutrition Action Group.
We have impressive neighbours. There is Duddingston Kirk, a faithful supporter of Holy Rood. In Bonnie Prince Charlie's house the Young Pretender himself is said to have resided, and the Sheep Heid is one of the oldest pubs in Edinburgh. Most of the people who live near the school are helpful, and understand that 930 young people each day will leave some traces of their passage.
Surveys tell us that young people are more environmentally aware than their elders. When the millennium tree-planting project came to Holy Rood, pupils volunteered in large numbers. The Holy Rood Green Team planted thousands of bulbs around the campus with their own hands. They will see the visible product of their efforts with the first green shoots of spring.
Inside the school, corridors and classrooms are well cared for by both staff and pupils. Environmental education is provided through geography, personal development and home economics. And pupils respond positively when the school environment is discussed. However, their ecological consciousness can slip a notch when their attention is rivetted on the gaudily packaged manna of the sweet shop.
Edinburgh Council is making a concentrated effort to support schools in the war against litter. A campaign team will soon visit all secondary schools with a strong environmental message. If it reduces the litter encountered in the green expanses of Duddingston, it will be most welcome. We hope that to see any litter on our school campus in the future, you will require bin-oculars.
Pat Sweeney is headteacher of Holy Rood High School, Edinburgh