THE PROBLEM was how to introduce the girls, 9 and 11, to real outdoor travel and camping without boring them to tears or marching them to exhauston. The solution was to canoe 28 miles along the South Fork of the Shenandoah with two overnight stops, the boats carrying the load andthe scene changing around each bend.

It helps if there is water in the river, but you can't have everything. The Shenandoah basin is in its second summer of near-drought; the protruding slate bones of the mountains forced us to get out every half-hour or so and drag canoes over what normally are gentle rapids.

Hundreds of people live along the Shenandoah between Luray and Bentonville and thousands of others canoe the river, yet it seldom takes more than a few strokes of the paddle to get out of sight of everything but he splendid river valley nd the birds and animals.

Those who read the papers will know that the river is closed to fishing because of mercury pollution, and at the rapids there are rainbows of paint scrapings from countless canoe bottoms; in some places the sharp edges ofthe strata have been ground flat.

Otherwise the party was alone with the ducks and woodchucks, and there was plenty of flat water for Karen and Laura to practice balancing and paddling while their father and the neighbor in the stern of the second canoe argued over bird indentifications. Among the diversions were whistling to bring responses from bob white quail and mooing back at cows.

The afternoon was hot and the river cool, so the girls soon were in the water, drifting in their life vests over the deeps and picking their way over the ledges, getting used to not worrying about wet clothes and muddy tennis shoes.

Then, quietly, Karen slipped slightly and came up streaming blood, her left palm slashed to the bone by an outcropping of slate.

The bleeding stopped quickly and the tears never started, but it was an hour of heavy paddling to the nearest phone. Her father worried all the while that the experience would sour her on outdoor life; Karen, it turned out, was worrying about whether the trip would have to be canceled.

Enter William and Louise Ruffner, who run a neighborly campground beside the river. A few cold soft drinks, their warm concern and the friendliness of their granddaughter Victoria made it almost disappointing when the time came for the ride to the Luray hospital, where Karen was taken in hand by a horn healer. The net effect of what could have been a disaster was to demonstrate that there are good people everywhere.

An hour an eight neat stitches later the girls were exploring an old graveyard while dinner bubbled in the stewpot. An important advantage of canoe camping is that you can take along no end of good things to eat and the equipment needed to prepare them; iron rations may satisfy the experienced camper, but goodies, plus sleeping cushions and spacious tents, are important for break-in trips.

The novelty of sleeping in a tent made the girls forget their customary nitpicking rivalry and in spite of suspension of the bedtime rule they corked off before the last of the light had faded. In the morning they woke so ravenous they put away a day's rations (an eventuality for which the neighbor had come prepared, having often taken his two strapping boys camping).

Just when the second day's paddle was beginning to grind came a dramatic thunderstorm with lashing rain, crashing thunder and 50-m.p.h. gusts that brought down branches uncomfortably close. Lesson 2: in the great outdoors, weather is something you live with rather than hide from.

Still, everybody was as soaked and chilled by the time the storm passed. The planned high light of the day washed out when no arrowheads could be found on the site of an old Indian town across the river from Rileyville usually a sure bet after a rain.

What could have been a dreary end to the day vanished in the excitment of Compton Rapid, the only one in the river that still runs with respectable white water, and in the discovery of Chipmunk Corner, surely the finest campsite on the Shenandoah. It was named by Laura for the chipmunk that scampered along the bank as though in welcome.

For some reason the several parties that had made camp earlier set up downstream from the sandy beach just below the rapid, leaving us to enjoy the view of the sweeping bend and sheef cliff and the oceanic roar of the water.

Firewood, hard to come by along most of the heavily-traveled river, was piled in great drifts on the far bank, and a canoe load supplied plenty for a fire that lasted far into the night and revived quickly at dawn.

What with toasted marshmallows, freeze-dried ice cream and a visit from a hoppy toad, Chipmunk Corner was not easy to leave; the pleasure of the night there lasted well into the hard paddling of the last day's headwinds.

Noticing that the men were beginning to flag, the girls incited a race, Laura paddling until her blisters popped and Karen spreading a plastic-bag sail whenever the wind blew fair. A glimpse of an immature bald eagle and the company of some bold buzzards helped pass the hours. A wood duck was kind enough to convoy her nine ducklings almost across our bows.

During the long flatwater stretch to the take-out at Bentonville the men wondered if perhaps it had been too long and tiresome a trip for the girls.

Their mother, raised in that earlier time when camping was a boy-thin, wouldn't have made the trip on a bet.

"Next time let's stay for a week," Laura said.