“Avalanche... heeeeeeelp!” The blood-curdling bellow echoed across the valley as four teenage boys skied over the lip of Col de la Leisse to find a man clutching his leg and howling in anguish. “Susie, my girlfriend... she’s buried... somebody get her out!” A chute of churned-up snow was strewn down the mountainside like builders’ rubble. It was a scene that every backcountry skier dreads.

But the boys kept their cool. In unison they switched their transceivers from “transmit” mode to “receive signal”. Toby found a stray glove on the snow and followed the fall line downhill. The injured skier was becoming hysterical, but Jack did his best to calm him down and get some facts: “How many people were unaccounted for? When did the avalanche strike?” Patrick heard a bleep from his transceiver, so Sebastian located the signal source, jabbing his probe into the snow until he hit something hard. Then the four of them dug furiously and had Susie out in the Val d’Isère sunshine within 13 minutes. Phew!

On this occasion, “Susie” turned out to be merely a transceiver buried in a backpack. The man with the “broken leg” was an instructor, Nick Parks, who had planned this avalanche scenario, a serious test of the skills he had been teaching his young charges during the previous few days.

Parks was impressed: “Not bad, guys. Your only mistake was not switching my transceiver off, so its signal didn’t get confused with Susie’s. But, luckily, you managed to get her out in time.” As they learnt, if a person is buried by snow, their chances of survival are about 90 per cent if they are reached within 15 minutes. After that the odds plummet.

My sons Toby, 16, and Sebastian, 13, and the two other boys had joined a four-day Teenager Backcountry Skills course that teaches off-piste skiing and mountaincraft to skiers and boarders between 13 and 17 years old. Off-piste experience was not essential, but fitness and a willingness to tackle anything thrown at them was expected. Clearly, this was not going to be the clubbing/sleeping holiday that attracts some teenagers to Val d’Isère.

At a precourse briefing, Parks, founder of the alpine adventure company Mountain Tracks, explained why he was running the course: “We have a generation of teenagers who are excellent skiers and thirsting for more. Of course, these youngsters are going to feel the need to go off-piste. My aim is to catch them young, because the typical avalanche victim is between 18 and 23 years old, a good skier, thinks he knows the lot, and is heading for the backcountry unprepared.”

Each of the boys was issued with a small backpack containing what Parks referred to as “the holy trinity” – transceiver, probe and shovel. “If you are caught in an avalanche, your chances are in the hands of your companions,” he said, “so you are going to learn how to use these.”

Next morning the atmosphere lightened as the group headed to the sun-drenched heights of Signal de l’Iseran, and ducked under the piste-side tape. I trailed in their wake, watching Parks lead the boys through untracked powder, spring snow, crud, breakable crust and ice – all during a single morning. “I had no idea there were so many different kinds of snow, and so many different ways to ski,” Toby said.

Most of the four days was spent off-piste. The vast Espace Killy ski area, which covers the resorts of Val d’Isère and Tignes, is ideal, with numerous lift-served backcountry trails to follow, some well-used itinéraires and other untracked routes through remote country, where a mountain guide is essential. One day they tackled the Tarentaise circuit, hiking with their skis over their shoulders to link with trails connecting the Espace Killy with neighbouring La Plagne and Les Arcs. They returned hearty, hungry and exhausted.

Parks taught the boys to “read the mountains” by looking for warning signs: high winds and sudden rises in temperature can set off avalanches. Once, I helped Parks to dig a hole into a wall of snow in which Toby curled up like a hibernating animal, out of sight of the others as they deployed the holy trinity to find and free him.

Toby and Sebastian will certainly be heading into the backcountry again. “Off-piste is awesome. After this sort of skiing, groomed runs feel like a theme park,” they said.

Hit the slopes

After last year’s disappointing snow in the Alps, the mood this winter is that things can only get better. The Ski Club of Great Britain says that the best bargains are likely to be in early April, when snow should be good and prices low because of an early Easter. North America expects a good season, with La Niña weather patterns likely to bring lots of the white stuff.

Season begins (key resorts):
Vail, Colorado, November 16;
Whistler, Canada, November 22;
St Anton, November 30;
Espace Killy (Val d’Isere and Tignes); December 1;
Three Valleys (Meribel and Courchevel), December 8;
Paradiski (Les Arcs and La Plagne), December 15.

Need to know

Mountain Tracks (020-7871 1858, www.mountaintracks.co.uk) will run three-day “teenager backcountry skills” courses in Val d’Isère/Tignes, starting on February 11 and 18, and March 24 and 31. The cost is £295pp.
Getting there: Martin Symington and sons travelled with Total Ski (0870 1633633, www.skitotal.com), which has chalets in Val d’Isère and Tignes. They stayed at the ski-in/ski-out Chalet Danielle in Val d’Isère, which costs from £559pp to £959pp for February 10 (half-term) departures. Flights from Gatwick or various regional airports, transfers and chalet board are included. Further information: Val d’Isère Tourist Office (00 33 4 79 06 06 60, www.valdisere.com)

If they are already competent skiers, how about trying:

Bobsleighing
Take their breath away hurtling down the bobsleigh track at La Plagne. The Mono Bob for age 16-plus is 100 euros (about £70). The Taxi Bob replica of the four-man competition bobsleigh is driven by a professional racer for 105 euros (over18s only). Families of all ages can take the four-seater Bob Raft for 108 euros per person with Snowline (0844 5573118, www.snowline.co.uk).

Snowmobiling
A guided snowmobile safari is a great way to go off-piste quickly (solo with UK driving licence, or as pillion passenger). Glide through forests and across frozen lakes in Finnish Lapland for a spot of ice-fishing. The excursion is 75 euros during a four-night, half-board stay in a log cabin at the Yllashumina Hotel with Inntravel (01653 617906, www.inntravel.co.uk). The package costs from £635pp, including flights.

Snowholing
Learn how to construct a roomy snowhole and survive a night in the wilderness. A day of winter skills training in the Cairngorms, using crampons and axe ice, is followed by an expedition to build the snowhole and a walk to Ben Macdui. For fit over18s (and over16s with a parent or guardian). Courses in January to March are £321pp for four nights (three in a lodge), full board, and transfers from Inverness airport or Aviemore station. Details: Mountain Innovations (0845 0956174, www.scotmountain.co.uk).

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