A dead pig is laid on the kitchen worktop at Penair Secondary School in Truro. Hovering above it is a young girl, hacksaw in hand, energetically sawing through the carcass. Holding the front trotters and overseeing the operation is John Rankin, 42, the school chef who is bringing butchery to the young. Whenever he gets hold of a lamb or a pig (usually once a month), he asks if any of the children would like to help him butcher it. Usually, about 20 volunteer.

But it doesn’t stop there. Twice a term, Mr Rankin orders in half a cow. For that demonstration, he may get up to 100 onlookers, including parents and teachers, gathered at the main counter after school.

“The kids are initially quite squeamish,” Mr Rankin says. “They think it’s a horror story. But once they realise there is no blood, it’s not a problem. They secretly love it.”

If the butchery workshops suggest that Mr Rankin may not be a typical school caterer, his menus confirm it. Pupils may be treated to haunch of venison, tandoori chicken, seared salmon, steak and ale pie, garlic snails, frogs’ legs or rabbit casserole - all fresh, all homemade and all as locally sourced as possible.

Every Thursday, the kitchen staff do something “a bit special”. That may mean a barbeque in the summer or warming “hedgerow” recipes in the winter, including game pie or pheasant in red wine sauce.

The school also uses these events to serve food from around the world. On Africa day, pupils tuck into zebra and ostrich steaks, camel curry, kudu fricassee and python simmered in cider. On Australia day, they sample freshly diced shark pie with puff pastry, as well as ostrich, kangaroo and crocodile dishes.

It is world-class world food - something that is rarely said about school dinners, even in the post-Turkey Twizzler era. So it comes as little surprise that Mr Rankin won the title of “Best dinner lady or man” at BBC Radio 4‘s Food and Farming Awards in November. The head judge, renowned chef Raymond Blanc, said it was the easiest decision of the night.

Not that Mr Rankin likes to be called a “dinner man”. He refers to himself as a chef, the pupils as his customers and the canteen as a dining room. “We serve restaurant-quality food,” he says. “I don’t serve anything that I wouldn’t be happy to pay for myself.”

But the prices are more tuck shop than Michelin-starred restaurant. Pupils pay no more than pound;2 per meal.

Penair’s snack bar sells pasta, pasties, sandwiches and pizza, and that helps to balance the cost of the more exotic main meals.

The school’s culinary philosophy is based on the concept of free choice. Pupils are not told what to eat, but since Mr Rankin’s arrival two-and-a- half years ago, they have followed their taste buds. The queue at the snack bar has shortened while the one at the “gourmet” counter has steadily increased in length. School lunch uptake for the main meal has risen from 30 to 300.

“If you force the kids to eat spinach or liver or things they don’t like, they will rebel,” Mr Rankin says. “They make their decisions based on taste, quality and what they feel like.”

Sometimes that will mean grabbing a panini that they can eat outside in the sun. At other times it will mean opting for a lovely warming lamb chop.

“On a miserable, cold day, I’ll cook a chilli con carne and hundreds of the little buggers will turn up for that,” he says in his Anglo-American accent that sounds more Australian.

But the school could not always boast such fine fare. When Mr Rankin arrived - as a temporary catering manager for just two weeks - the minced beef “looked like worms” and the diced meat always came from the worst part of the animal. Coley fish, an unpopular member of the cod family, was frozen, as were all the vegetables.

“We have a big steamer in the kitchen, but all the vegetables were boiled in massive vats for two hours. It was just mush. I wanted firm, fresh produce.”

But first the young up-start had to get his views accepted by the dinner ladies, some of whom had been working at Penair for more than 20 years. Not all of them were keen on change. “I was outnumbered,” Mr Rankin remembers. “There was a `Who are you to tell me what to do?’ kind of attitude. Eventually, the kids spoke for me. They wanted different food and I showed the team how to produce that. Since the award, the kids have become proud of the school and its food. Both they and the dinner ladies have come round.”

But the pupils are not merely passive recipients of a delicious menu. They are involved in the whole process, from planting, foraging and reaping to preparing and cooking. One day a week, a dozen or so disruptive Year 7 and 8 pupils leave their lessons to help with Mr Rankin’s “Let’s get cooking” and “Kitchen club”, which he runs with Simon Merrick, the head of ICT.

Joe Tann and Derryn Pendleton, two Year 8 boys, have been involved in the classes for a year and have helped to build the school’s kitchen garden from scratch. They had to lug tonnes of earth and compost, well before they could grow and maintain the vegetables. Finally, they were able to cook and serve what they had sown.

The boys are now mentors to the younger pupils in the club. As a group, they have gutted mackerel and filleted ling. They then prepare and season the fish with dill, basil, oil or butter. When it is served to the school the next day, they feel a sense of pride.

“They have both settled down a lot,” says Mr Rankin. “Instead of getting into fights, they are looked up to now by the younger pupils. I think it’s because they feel part of a process. It’s turned them around.”

More pupils will be able to get involved now that the school head has signed over two acres of land and an old greenhouse to the kitchens. It is all part of Mr Rankin’s masterplan to make the school more self- sufficient. By the end of the summer, he hopes to grow 30 per cent of the food Penair uses - largely salads and soft vegetables.

What is bought in is sourced as locally as possible. Fish comes from St Ives and Newlyn, meat from Cornish company Etheringtons and most vegetables and fresh produce is grown within 10 miles, supplied by Westcountry Fruit Sales.

A nearby estate supplements their supplies, donating three whole deer a year. Another, Tregassow Manor, provides as many pheasants as it can eat during the winter. It all helps keep the costs down. “All we want it to do is break even,” explains Mr Rankin. “We pay our staff and our suppliers, and that’s it.”

It angers him to see large corporations and outside caterers “exploit” children - making large profits regardless of quality. “All our money goes back into the food,” he adds.

“Our ethos from the beginning has been to be here for the kids, not to blindly take their money.”

But it is difficult to know where the school can go from here. Penair may own 54 acres of land, but space is at a premium inside. It already feeds half of its 1,300 pupils each day - a triumph in the face of a lunch-box culture that all too often fails to meet nutritional standards, according to a recent study by Leeds University.

But its dining room only seats 143 people, so the majority of pupils are forced to choose the quick takeaway option rather than the main sit-down meal. “It’s sad for the school,” says Mr Rankin.

“Because of the timetable, it’s almost impossible to have split lunch sittings. The pupils don’t want to queue 20 minutes for a main meal and I don’t blame them. We have become a victim of our own success.”

The school cannot increase uptake without a rebuild or adding an extension to its dining room, but no funds are forthcoming and the situation will only worsen as pupil numbers grow. The team is also constrained by the kitchen, which has not been updated for 30 years.

But Mr Rankin feels unstoppable. “I want to do more and more,” he laughs.

To the doubters, his message is clear: good-quality school food is possible, even when resources are limited. “Have a bit of courage,” he says. “You can’t say it can’t be done because we’ve done it. Even with a tiny dining room and 30-year-old equipment, we won a national award.”

Mr Rankin is happy to advise other schools, but not all seem ready to embrace change. Before the award, he invited 30 local catering managers to share best practice, but only six accepted and just one showed up. Now the response may be different.

“A lot of schools think they know what they are doing,” Mr Rankin says. “They see themselves making pound;11,000 a year profit from food and think that’s a success, but they are not considering the quality.”

Instead of using school kitchens as a “cash cow”, Mr Rankin is content to come in under budget and pour any additional funds back into imaginatively cooked, high-quality fresh produce. Choice need not be abandoned, he insists: the pupils will vote with their lunch money.

And the proof? Look no further than the hundreds of pupils at Penair who are rejecting fast food for a nice little venison pie. When it tastes this good, they would be mad not to.

John Rankin’s CV

• 2007-present: Two-week catering manager post at Penair School; has been there ever since.
• 2006-07: Chef in and around Newquay.
• 2004-05: Pubs and restaurants around England.
• 2000-03: Returned to England before moving to Austria, where he worked as a raft guide in the summer and as a chef in a ski resort in the winter.
• 1986-2000: White water raft guide in Tennessee. Learnt how to cook for hundreds of customers on the banks of the river.
• 1984-85: Left Dury Falls School in Hornchurch, Essex, aged 16, to go to Sante Fe, New Mexico, as an exchange student.