Boarding school was a family tradition for Clay Gibson. As a teen, he followed his brother, uncle and great uncle to Baylor School, a 112-year-old private school in Chattanooga, Tenn., whose 670 acres overlook the Tennessee River. Thirty years later and now an Atlanta law-firm partner, Mr. Gibson is a Baylor trustee and easily lists the elite school's many attractions.

But when time came to send his three children to high school, Mr. Gibson broke with tradition: He sent his two sons and daughter to a private day school. He loves Baylor, he says, but he and his wife never seriously considered it. "We're very involved in our kids' education and life, and we wanted to stay involved on a day-to-day basis," Mr. Gibson says. "We wanted them to stay in our home and enjoy that opportunity."

Mr. Gibson's decision is part of broader shift plaguing schools like Baylor: While enrollment at private day schools is booming, boarding schools are seeing little or no growth. Boarding-school enrollment stands at 39,000 for the 2004-2005 school year, and has barely budged in five years, says the National Association of Independent Schools. That's down from about 42,000 in the late 1960s, estimate some boarding-school veterans. (The association doesn't have historic figures.) Enrollment grew 2.7 percent over the past 10 years, versus 15 percent for private day schools.

Boarding-school administrators often blame image problems and competition from day schools. But a growing number of administrators, consultants and parents believe the biggest force at work is a shift in parent philosophy over the past generation. With more mothers working outside the home and with older couples having fewer kids, parents want to be more involved with their children than their forebears did, they say.

"The type of kids who used to go to boarding school has a very different relationship with their parents," says Kelly Makes of Atlanta-based Mindpower Inc., a consulting firm working with Baylor. "Kids are very close to their parents. They are not as independent." Adds Alice Jackson, a California consultant who advises families on boarding-school issues: "I think parents have become more dependent on their children."

Boarding schools have educated legions of this country's wealthy and powerful. They invoke images of rich endowments, bucolic campuses and reputations for providing the best education money can buy. They are among the oldest educational institutions in the U.S., surviving the Revolutionary War and the revolutionary 1960s, when anti-establishment youths boycotted them.

Some of the most famous boarding schools, such as the Phillips Academy Andover in Massachusetts and Phillips Exeter Academy in New Hampshire, still get many applications for each opening. And boarding schools for children with learning or behavior issues are a growth industry.

But many traditional boarding schools say their prospects are worsening. "It's very critical because other alternatives that are close to home are emerging," says Patrick Bassett, president of the National Association of Independent Schools, which represents private day and boarding schools. Home schooling and faith-based schools are among the options attracting families, he says. Boarding schools "have to make a better case for themselves."

To boost their case, boarding schools are hiring marketing consultants, overhauling catalogs and advertising more. The newly minted Association of Boarding Schools has hired a Chicago-based public-relations firm to help make its pitch. Many schools are wooing teens directly. Baylor, for example, uses its Web site to appeal to kids and has beefed up its program for inviting prospective students and parents on-campus.

Fifteen years ago, heavy recruiting tactics were unheard of in Baylor's red-brick corridors. Funded by the scions of the Coca-Cola bottling empire, Baylor for decades had to do little more than wait for the children of Southern gentry to land on its doorstep. Its alumni include Mercer Reynolds, a former U.S. ambassador to Switzerland, and Arthur Golden, author of the best-selling novel "Memoirs of a Geisha."

While Baylor's day-student population has about doubled over two decades to 859, partially reflecting the addition of sixth-graders to the school, the number of boarders has grown by 15, to 185. Three years ago, the school, aware that disproportionately large day populations can make it harder to recruit boarders, began to focus in earnest on boosting the number of its live-in students.

Boarding schools like Baylor have strikes against them. They are expensive: Average tuition topped $31,000 last year, versus $16,300 for day schools, says the independent-schools association. And there's the image problem: Many boarding-school officials believe their schools suffer a negative image as repositories of maladjusted wealthy children angry at their distant parents or from broken homes.

"We're portrayed over and over again as a breeding ground of the elite wealthy, or perhaps the dysfunctional wealthy," says Michael Mulligan, head of the Thacher School in Ojai, Calif. What's more, day schools are increasingly offering the exclusivity and status that were once the domain of boarding schools.

But Baylor's top brass thinks the trend has as much to do with a new generation of parents that don't want their kids to leave home. That was the case with Bert and Sharon Moffatt of Burlington, Vt. Last summer, they had a sudden attack of cold feet just weeks before their daughter, Shannon, 17 years old, was to attend Baylor as a junior. The couple had initially encouraged the move, noting the school's extracurricular activities, such as its well-regarded swimming program, and its 8-to-1 student-teacher ratio.

But as the Moffatts began to draw up Shannon's packing list, the reality of their only child's departure set in. The family debated for weeks over the summer, asking Baylor to let them delay a decision. They finally chose to send Shannon to a local private school.

After her parents' about-face, "I was definitely mad," says Shannon, who was looking forward to boarding. "I've always gone to school with the same kids," she says, noting that her school is "very small."

But her mom doesn't regret it. "I just felt it was an opportunity to have her here a few more years to really, really know our kid inside, and hopefully impart a piece of our values before sending her off into the world," says Ms. Moffatt, deputy health commissioner for the state of Vermont. "I've worked ever since Shannon was 6 months old, and I feel like, in some respects, I haven't had all the time I want to have with my child." Now, she says, "I get two more years."

Brooks Taylor, a Baylor alumnus in Birmingham, Ala., says he initially encouraged his oldest son to consider boarding. But he changed his mind once his son, Brooks Taylor Jr., showed interest.

"I think Mom and Dad pretty much decided he was going to stay home," says Mr. Taylor, who was surprised by his own change of heart. "It was more our need to feel like we had done our best in imparting the wisdom of the world to him."

Boarding schools are trying to battle back. One task is tackling stereotypes. The boarding-school association recently published a survey, dubbed "The Truth About Boarding School," suggesting boarding doesn't deserve a tarnished image. In the survey of more than 2,700 students and grads, 95 percent of boarding-school respondents said their lives didn't revolve around drugs or alcohol, compared with 82 percent of private-day and public-school respondents. Among those from boarding schools, 26 percent said there was "some cheating" at school, versus 60 percent for private-day-school respondents.

Mr. Bassett, at the National Association of Independent Schools, says "there's no simple formula that can determine whether boarding school or day school is better overall."

Boarding schools are marketing more heavily. Asheville School in Asheville, N.C., is marketing its summer programs more heavily in hopes that parents, after seeing their kids in summer school, will warm up to the idea of year-round boarding.

Like other schools, Asheville is fighting the parental-philosophy shift by touting the notion that a little breathing room can be good for teens. It is producing a direct-mail DVD showing vignettes in which boarding students overcome challenges and achieve personal growth. The message: Boarding is a way for parents to give older teens more responsibility in a structured setting.

"Parents learn from the culture they ought to be attending to every detail of their child's lives," says Pete Upham, Asheville's assistant head. "We want them to learn independence and freedom."

Boarding schools have also discovered it pays to appeal directly to students. "Parents used to drag kids to see boarding schools," says Gregg Maloberti, dean of admission at Lawrenceville School in Lawrenceville, N.J. "Now kids drag their parents."

Abby Kraft is one such kid. Amy and John Kraft of Beaufort, S.C., were shocked when friends sent a daughter to boarding school. "What kind of horrible parents would do that?" Mr. Kraft recalls thinking. But after seventh grade, their daughter went to summer camp at a boarding school -- and started campaigning to attend boarding school in the fall. The Krafts refused. "She is our only child. Our lives truly center around her," says Ms. Kraft.

"They didn't want to give me up," says Abby, who even crafted a PowerPoint presentation in her efforts to change her parents' minds. "It took a lot of information and time to convince them." After receiving a scholarship from the school, Abby went to Baylor. She will be a sophomore in the fall.

To reach students directly, boarding schools are investing in the medium with which many kids spend the most time: their computers. St. George's School, Newport, R.I., is overhauling its Web site, inserting video clips of students and teachers talking about school life. "Experience! Fun/Experience! Adventure/Experience! Baylor," begins Baylor's animated Web site aimed at enticing kids to its summer program.

Baylor uses an arsenal of other pitches to appeal to students and make boarding more palatable to parents. The school says it contacts each applicant to its boarding program 10 to 12 times, to give them as much information as possible before making their decision.

In a wood-paneled conference room, Baylor administrators recently made their case to a group of middle-school students and their parents. Baylor Dean Dan Morrissey talked about the "residential life curriculum," a new marketing phrase to sell the idea that living away from home is a form of education. In a PowerPoint presentation, he noted the many adult mentors who support students, including the "hot chocolate lady," a Baylor staffer who usually has the drink available for teens who stop by her office to chat.

He cited statistics, comparing those who live at the school with those who attend its day program: Boarders make up most of the string orchestra; seven boarders are on the 14-member honor council; boarders were homecoming king and queen this year. He ended by citing a parent's testimony that "I feel assured that my daughter is in caring hands."

Afterward, buses took parents to Sticky Fingers, a barbecue restaurant. There, parents of current Baylor students talked with those considering the option. Sitting in a wooden booth, Rahul Dixit, whose son attends Baylor, noted another factor that drives some parents away from boarding school: peer pressure. Mr. Dixit, a Lexington, Ky., physician, vividly recalled some of his friends' reactions when they learned his son was going away. "Horror," he says. "The hardship is that you're sticking out."

Therapists who treat adolescents say boarding school, like any school, can be a great or terrible choice, depending on the child, school and family. For some, it may offer teens a chance to grow. "In recent years, we've been seeing more kids who have had overinvolved parents, who have been overprotected," says David Fassler, a clinical associate professor of psychiatry at the University of Vermont.

Mark and Ellen Robey of Dearborn Heights, Mich., sit on opposite sides of the debate. A Baylor graduate, Mr. Robey says he is "greatly thankful" to his father for having the "guts" to let him leave home and become more independent. He says his parents made a sacrifice they realized would benefit him. When he left for Baylor, "it was one of the few times in my life that I saw my father cry," Mr. Robey says

But his wife, a clinical social worker, thinks differently. "As parents you are responsible for raising your kids," she says. "In my field, I see kids who need emotional support and family support, and as best as boarding schools try, they aren't able to provide that." She is holding sway: Mr. Robey says sending their two teen daughters to boarding school "isn't on the table."