At Les Arcs 1800 you can see foxes and stoats - if you know where to look. By Stephen Wood
Michel Buet, ski-school director at Les Arcs 1800, led me down towards the resort. Then he turned off the piste and we skied across deep snow to a little copse. Here he took off his backpack, pulled out a shovel, and started digging. Ten minutes later he was standing in a hole with his feet on the sod and his shoulders level with the surface of the snow. Why did he do this? Because I asked him to.

Buet runs a course which, as far as he is aware, is the only one of its kind in the Alps. His Ski Nature course (also called, poetically, l'esprit du renard, "the spirit of the fox") lasts for one whole day and four half-days, and costs 690 francs (pounds 77). Buet also plans to experiment with shorter versions.

Forget the days you have spent with other ski guides and instructors: on Ski Nature, Buet doesn't lead you down steep couloirs or over blind jumps, or tell you to bend your knees. Rather than exploring your skiing abilities, his course explores the mountain environment. There are sessions on mountain flora and fauna, snow structure, and the natural hazards of the mountains; each one is combined with a little adventure on skis. The full day trip involves a journey on a horse-drawn drag-lift into the Vanoise national park, which abuts the Les Arcs ski area - where, Buet promises, you will see wild chamois and bouquetins (stoats).

What led Buet to devise the course was partly, he admits, the limited challenge of being a ski teacher: "Up and down, left and right - I've been doing it for 20 years." More important was the desire to pass on "all the other stuff we learn while training to be a teacher. It's such a waste not to share that knowledge with people who come here to ski." The fact that he has two children heightened his interest in educating skiers on safety.

On a short trip to Les Arcs last month, I didn't have time for the whole Ski Nature course. But Buet, a shy, charming 41-year-old with a sense of humour which keeps trying to burst through his reserve, gave a group of us a half-day sample of it. And we had a terrific morning.

First, there was the unusual pleasure of using skis for the purpose for which they were designed - as a means of transport. In the spirit of the wild fox, which dislikes populated areas, Buet led us away from the pistes on a long traverse through the forest. Picking our way through the trees was not easy: my skis felt about a metre too long for the tight turns. During the frequent rests Buet identified different trees and pointed out animal tracks, mainly those of rabbits and foxes.

Secondly, the valley was transformed from a 30-year-old ski area into a patchwork of ancient mountain communities. Buet pointed out the village which 200 years ago had a school for mining apprentices; a bare hillside had had its trees cut down in the late-19th century to make pit props for a salt mine. When he spread out a detailed map on the snow to show us the lie of the land, it struck me what a pitiful thing a piste map is: using it as your guide to the mountain environment is a bit like exploring Paris with only a Metro map.

The long traverse through the forest took us to an exquisite early-18th- century chapel, Notre Dame des Vernettes, built on the site of a spring with miraculous properties. Penitents came on pilgrimages to the chapel from as far away as Tignes, struggling up from the valley; we felt rather smart having travelled down to it on skis, and then being able to traverse back to the nearest ski lift.

Over lunch (if you go to Les Arcs, don't miss Chez Lea in the hamlet of Le Planay) Buet told me about the part of his course where he digs a hole to reveal the structure of the snow. I persuaded him to give me some personal tuition on the way back to Les Arcs 1800.

The walls of his hole revealed the history of this season's snow. The heavy fall from late November was still fairly intact, because the ground temperature had remained constant; a rise in temperature would have degraded the crystals and destroyed the "branches" of its tree-like structure, an effect which can lead to avalanches: subsequent layers of snow tend to slide off the top. But the evidence of two rain showers in early December was clear: two thin sheets of hard ice with a light snowfall sandwiched between them. The skiing surface, 25cm of snow from mid-December, covered up the season's previous history.

Have you ever thought about the hidden depths of the snow beneath your skis? Neither had I. You learn a lot on Michel Buet's Ski Nature course.

For details of Ski Nature, call Erna Low on 0171-584 2841. The course involves intermediate-level skiing.