When Gail Kahn talks about her job teaching gifted children at Alexandria's George Mason Elementary School, she speaks as if she were a combat veteran. Her conversation is sprinkled with the words "bombarded" and "hardened," and she speaks of worrying constantly -- not about her students, but about the calls and visits from parents battling to get their children into her class.

"Over the years I have had to become a much stronger person," she said. "I think the parents are great, but lots of them want what is not possible for their child. You should try telling someone her daughter isn't gifted."

Begun as part of the educational push that was prompted by the launch of the Soviet Sputnik satellite nearly three decades ago, programs for gifted and talented students have been developed in thousands of school districts across the United States. But even as the programs have grown in scope and number, the debate has intensified over which children are entitled to the label "gifted" and what the programs should accomplish.

Education experts generally agree that programs for gifted and talented students have kept many brilliant children happy in public schools and have challenged children who might have become bored. At the same time, some educators argue that the definition of "gifted" has become so vague that it is almost meaningless except as a status symbol for ambitious parents; some believe that the programs are by definition elitist and exclusionary and should be opened to more students, not fewer.

Most school systems in the Washington region place at least 10 percent of their elementary school students in classes for the gifted. Alexandria places the highest proportion locally -- 19 percent. That stands in sharp contrast to the rest of the country, where the average is less than 3 percent, according to the Council for Exceptional Children.

"When you have 20 percent of your students in a gifted program, you don't have a gifted program," said Beatrice Cameron, assistant superintendent in charge of programs for gifted and talented students in the Fairfax County school system. "Every kid begins to look more and more like the last child. These programs should be for people with very different instructional requirements."

Programs for gifted and talented students bloomed during the 1960s and 1970s in an attempt to provide special instruction for those few students -- usually judged to be in the top 5 percent of their class -- so advanced that they found even accelerated course work too restrictive.

Today, the curricula vary widely. In some schools the gifted and talented students use the same textbooks as children in regular classes. At George Mason, gifted fifth graders write computer programs while their classmates down the hall learn how to use them. And Kahn's writing students are making books, written out in longhand on brightly colored paper, while others learn to read.

More than 1 million public school students have access to some program for the gifted and talented, according to the National Association of State Boards of Education. Twenty-seven states each spend more than $1 million a year on such programs; in 1976, only eight states spent that much.

Beginning this fall, Virginia, which has become a national leader in working to educate exceptional students, will require every school division in the state to offer classes for gifted and talented students from kindergarten through eighth grade.

But although the net has been cast deeper and wider each year -- more than $200 million will be devoted to teaching gifted and talented students in the United States in 1985, or 15 times the amount spent in 1972 -- controversy and doubt about programs for the gifted and talented have come in equal measure.

The definition of programs for the gifted and talented has become so broad that no uniform criteria for admission to such classes is possible, educators say. Few systems in the Washington area rely solely on test scores; recommendations from parents and teachers, leadership evaluations and performance ability are often taken into account.

"No one is really sure about what we mean by the term 'gifted,' " said Elizabeth McClellan of the Council for Exceptional Children. "It's such a slippery term."

The Alexandria School Board recently wrote to the state Board of Education and questioned the validity of requiring classes for gifted and talented children in kindergarten through third grade.

"We find no documented educational reason for identification of talented 5- and 6-year-olds," the letter said. "Indeed, this particular aspect of our national focus on education seems to be on a collision course with the needs of young children in school."

In Alexandria, as in other cities, officials are concerned with their ability to evaluate children effectively when they are that age.

"Who is the gifted 6-year-old?" asked Lou Cook, chairman of Alexandria's school board. "As far as I am concerned, at the age of 6 the kid who throws the rock through the window could be the one."

School systems in the Washington area take differing approaches in their programs for the gifted.

Fairfax County, which spends more than $1 million each year on programs for the gifted, has the widest range in the area. Each of the county's elementary schools has enrichment centers where children identified as being gifted receive at least two hours of additional instruction each week, according to Margaret Richardson, director of student services for Fairfax County schools. The schools offer separate centers with specialized curricula for the most talented students.

In Montgomery County there is a different blend of programs. Several elementary school teachers rove from school to school to work with gifted children one day a week.

The District has no comprehensive plan in place but plans to implement programs for the gifted and talented in every elementary school by the 1985-86 school year, according to Phyllis D. Hines, director of the programs for the District public schools.

There is a rationale for each approach. The Texas-based Sid W. Richardson Foundation has just completed a survey of more than 1,500 school districts with gifted programs. It found a hodgepodge of offerings and has recommended replacing them with an in-class "pyramid" of options at each grade level. The foundation says that the net should be broadened to include more -- not fewer -- students.

The recommendation reflects a concern voiced by some educators that the problem with programs for the gifted is not that they are available to too many students, but that they are available to too few. Ever since the programs began, in fact, the accusation has been made that a program for the gifted and talented that selects only the top few students is unfair.

"What exactly are we trying to accomplish here?" asked Helene Gerstein, a professional development specialist at the National Education Association. "I worry about the elitism of programs for the gifted and talented , of taking the cream of the crop and isolating them from the rest of the students. There should be ample opportunity in regular classrooms to pursue most studies."

"This field is just shot through with problems," said Joseph Renzulli, associate director of the Bureau of Education Research at the University of Connecticut. Renzulli is well known for advocating that a large number of students -- he puts the figure at about 25 percent of the total -- need more enrichment opportunities. And he is strongly opposed to strict standardized definitions of the gifted.

"Nobody has ever successfully argued that you need a 135 IQ to be creative," he said. "I believe in the 'I will' and the 'I can' as much as the IQ." He and many other educators say that relying on test scores -- as many programs for the gifted do -- discriminates against minority students who are underrepresented in programs for the gifted and talented.

The conclusion of the Richardson Foundation report, shared by many educators, is that a focus on special programs for only the top few students will take programs for the gifted in the wrong direction. But others continue to worry that the trend toward broader definitions will harm the students who truly need help.

"There is a misunderstanding about democracy here," said Camilla Benbow, assistant professor of sociology at Johns Hopkins University. "Democracy isn't giving the same thing to everybody, it's giving opportunity to everybody. A gifted child in a regular classroom has no opportunity. Someone with a 140 IQ is as different from the the rest of the kids as someone with a 60 IQ. Nobody should ever dream of putting either person in a regular class."