There will be swimming and sailing and horseback riding when Camp Letts opens again for the summer. There will be arts and crafts and nature hikes, a few cases of poison oak, several spats among bunkmates, and the requisite number of homesick souls.

But this year, for the first time in five summers, there will not be a computer program at the popular Edgewater, Md., camp, operated by the YMCA of Greater Washington. The 1,400 area children who attend Camp Letts, the largest summer camp in Maryland or Virginia, have made their vacation tastes known: They prefer canoeing to computing.

"There was a waning interest, not a growing interest, in the computer program," said Pat Butcher, the YMCA's senior vice president for camping services.

"It seems to me that parents these days want to provide an experience for their children when it comes to camping," Butcher said. "They're looking for something special that will stand out in the minds of the kids -- the memory of a special relationship with a cabin mate, the experience of sailing competitively -- rather than another developmental program."

It's that time again. Within the next few weeks, an estimated 4 million children and teens in the United States, including thousands in the Washington area, will pack their bags, bid the family farewell and head to summer camp.

The campers will find a renewed emphasis on time-honored group activities at many of the 11,000 camps across the country. Their parents, on the other hand, will find themselves spending more money to give their children the summer camp experience, mainly because of rising insurance costs.

What nobody is likely to find is the same enthusiasm for computer instruction and computer games that had been fashionable in summer camps for most of the decade.

Computer camps, along with hundreds of computer programs within traditional camps, reached the height of their popularity in 1982 and 1983, when computers were being introduced into schools, according to national camping officials. The only comparable trend came in the late 1950s and early 1960s when Americans, troubled by the Cold War and increasingly aware of the rest of the world, briefly popularized foreign language programs in summer camps.

In 1983, more than 300 camps were devoted primarily to computer science, said Jim LeMonn, spokesman for the American Camping Association. Now, there are fewer than 100 such camps, he said, and the numbers are rapidly dwindling.

"I had expected to see business camps where the kids study accounting instead of archery, but it didn't happen," said Paul Johnston, who heads the Advisory Service on Private Schools and Camps, a consulting firm in Bethesda.

"Computers are a good rainy-day activity, but kids get so much of them at school these days, they don't really want to spend the summer that way," Johnston said. "What I see is a lot of folks working two jobs, hustling a lot. They see what's happening to their kids, and they want to give them a break. They want the summer to be a time of year when the kids aren't going to be frazzled."

Chris Fink, 11, and his brother Michael, 12, of Gaithersburg are veteran campers. They have been regulars at Hope Valley Camp, a rural Frederick County outpost sponsored by the Council of Churches of Greater Washington, for the past four years.

"It's pretty fun," Chris said. "You get to do different activities like swimming and playing basketball and playing with your friends in the woods. You learn a little bit about nature, like leaves and trees and things and poison ivy -- I got that all over me last year.

"The only thing that's not so great is having to sleep on bunk beds," he said. "They get you up early, and you don't feel like getting out of bed. It's fun to be away from home, though. Some kids get homesick. I don't."

His father, Robert Fink, has the typical parental view about camp: He wants his sons to get plenty of fresh air. He wants them to learn how to get along with other people, how to live happily in a group. He likes the idea of a break in their summers.

"As soon as school gets out, they see their friends and have a great time. Then, after a month, they're bored," Fink said. "Camp is a different experience for them. They get to have some free time, I have some free time, and I don't have to worry about what they're doing."

The prototype for the summer camp dates back 126 years. In 1861, Connecticut schoolmaster William Gunn led a group of students on a 40-mile trek to the beach, where they camped for two weeks. By 1876, Dr. Rothrock's School for Physical Culture in eastern Pennsylvania was advertising its summertime "outdoor experiences for weakly boys."

Five years later, the first summer camp as we know it, Camp Chocura, was established in Easton, Maine, to promote the "ideals of physical fitness, work, responsibility, love of nature, honor and fun," according to its educator-founder.

James C. Stone, a professor of education at the University of California at Berkeley, recently completed the first known study of the effects of camping on children and found that those ideals still hold. His results, based on a survey of camps in Maine, Texas, Minnesota and California, indicated that campers made "statistically significant gains" in such areas as decision-making, self-concept and interpersonal relations during their summers away from home.

"The parents said they sent their kids to camp, first, because they wanted them to have a good time, but also because they want them to be better human beings," Stone said in a recent interview. "We can confidently say that camp affected children positively, and we can say that about very few institutions these days."

In the Washington area, most young campers gravitate toward two-week sessions at facilities in Maryland, Virginia, West Virginia, Pennsylvania and western North Carolina, said Elizabeth Sibbett, director of the Camp Advisory Service in Monrovia, Md.

Their options range from small rustic spots with outhouses to such sprawling complexes as Camp Friendship, on 460 wooded acres in the town of Palmyra, Va., between Charlottesville and Richmond.

Friendship, which draws 1,300 campers each summer, features a basketball pavilion and covered riding ring, a new lithography program allowing campers to print the camp newspaper, and a contingent of 16 counselors from foreign countries.

Camps specializing in tennis, sailing, weight loss and drama are still in demand, Sibbett said, "but many people have called me and specified that they definitely don't want computers."

Traditional all-around camps have shown renewed popularity over the more expensive speciality camps, she said, partly because of rising costs. A camp that charged $350 for a two-week session four years ago, she said, may now cost as much as $495. Still, prices vary. Letts, for example, costs $455 for two weeks; Friendship charges $595 for two weeks, and Hope Valley costs $225 for 12 days. For children from lower-income families, some churches and other groups provide scholarships to help offset the cost of camp.

At the Miers household in Bethesda, nobody believes it is time to get ready for camp again. Sarah Miers, 14, is bound for a theater camp in upstate Pennsylvania; Rachel, 8, for the riding course at Camp Friendship. Martha, 8, who attended Friendship last year, has decided to stay home this summer.

"I can't wait. I love my camp," said Sarah, who had just received a letter from one of her camping friends. "If I wasn't going to camp, I'd probably be playing a lot of tennis this summer. And I'd be really bored."