Swoosh! Skiing-whether downhill or cross-country-is a fantastic family activity. Here's what you need to know before you and your kids hit the slopes.

Downhill skiing

Know the benefits. Downhill, or alpine, skiing appeals to a lot of families because it's something they can do together, whether for winter weekends or a week's vacation. "There is a real thrill to skiing, and it develops core strength, coordination and balance," says Peter Ingvoldstad, snow sports university director at Smuggler's Notch in Vermont. "Plus, because you're around a lot of other people on the slopes, skiers have to be conscious of their manners and relating to others."

What's suitable at what age. "A lot of kids start at age four," notes Patty Bennett, family center director at Bretton Woods, NH. Children start off without poles to learn how to handle skis properly. Once they've been skiing for a couple years (say, by age 6) and are on intermediate terrain, they'll use their poles to help push themselves along flat stretches. Lessons often last two hours or more-most half-day or day-long programs have a "snow play" approach where they learn ski skills, but also have time to build snow forts and warm up with snacks (and even a nap for younger kids) indoors. Ingvoldstad adds that even three- and four-year-olds can ride basic chair lifts after they've learned how to use them safely and have taken a few trial trips with an adult. "My advice is to walk around a ski area with your child before you sign up for lessons. I did this when my sons were three and they weren't ready yet, but by four they were," says Melissa Banks of Westminster, MA, mom of Zachary, 7, and Jacob, 5.

The equipment. Buying new ski poles, boots, bindings, goggles and a helmet can quickly add up to $500 or more, so consider renting equipment for kids on a weekly basis or lease for the season. Buying secondhand equipment is also a good option - but don't go for the really old stuff. Ingvoldstad notes that ski shops have to follow strict standards for equipment safety so, for example, if the bindings on the skis are old, they will not adjust them. Bennett says not to buy equipment that's too big either, which will only make it harder to ski.

A ski stood on end should reach between the child's chest and chin for beginners, and between chin and nose for more advanced skiers. "Ski boots are fairly heavy and very rigid, so kids who have never worn them will say they're too tight," she says. "They should fit snugly and the child's toes should be flat." As for helmets, they are not mandatory, but most experts strongly recommend them. Modern helmets are light, comfy, help keep you warm and are available in cool designs, like moose antlers. Visit http://www.lidsonkids.org/ for more details. Other equipment essentials: Sunglasses or goggles, a pair of warm socks, a jacket and snow pants, a neckwarmer and good mitts.

Choose an approach. As in most sports, you can teach your child yourself, but group classes are social, teach skills correctly and can be a good way to get the basics down. "I can't believe the skills that my older son has developed at his lessons at Wachusett Mountain; I have to keep up with him now!" says Banks. It's great, but not crucial, for instructors to be certified (in the US, Professional Ski Instructors of America; in Canada, the Canadian Ski Instructors' Alliance). Look for an approach that stresses safety as well as fun-for example, trying to step on a balloon tied to a leader's ski boot to learn how to keep skis parallel. Downhill skiing can be expensive-a day-long lesson can cost upwards of $100.

Be safe. In addition to properly fitting equipment (kids shouldn't wear dangling scarves or hats), warm moveable clothes and a helmet, your child should always wear an SPF of at least 15 - reapplied every two hours - even on cloudy days, as the sun's rays can be extra-intense against the snow. Pay attention to temperature and windchill, avoid frostbite by covering exposed skin and heading indoors on extra-cold days (below -13F/-25C with or without windchill), and only stay outside for a reasonable amount of time, based on weather conditions. Ski lessons should include info on how to ski in control, minimize falls, treat other skiers, use the chair lifts properly and where to meet up if separated. Some families use handheld radios (turned off during a lesson!) to keep in touch.

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