"The coach used to brag about how much he drank after work . . . . A couple of times he caught us vandalizing, drinking, smoking pot, but he just looked the other way. He bought us a case of beer after a big game--he just wanted to be one of the guys."

The young man, invisible behind a curtain, was one of three anonymous Fairfax County teen-agers whose "jock" images had helped to disguise their drug use at school--and who yesterday, at the request of school officials, told their coaches so.

"I skipped a whole quarter in some courses," the first student said, "but it was always okay. Just so long as you're winning, winning for the team."

The voice was flat, but his audience flinched. Fairfax County Superintendent William J. Burkholder, who had assembled more than 400 high school coaches, athletic directors and staff at Robinson Secondary School, listened impassively to the students' stiff, tonelessly emphatic testimony.

A husky-voiced teen-aged girl, a former soccer player who said she "always did my homework, always went to class . . . to con everybody," recalled playing once "so drunk I couldn't even catch the ball." Although the students were speaking from backstage, her amplified voice seemed to hang over the main microphones.

"Nearly everyone on the team that year was doing some kind of drug," she said. "We got drunk in the locker room--usually hard liquor . . . The coach used to joke around with us about late night parties and staying out all night."

No names were used, no schools mentioned. Burkholder waited a moment in the silence that followed, then made his pitch.

"Sports and drugs are no longer mutually exclusive in our schools, any more than they are among professional athletes," Burkholder said, his usually somber voice hammering a little heavier with each sentence. "Your special relationship with the kids gives you greater personal insight than most teachers and more objectivity than most parents . . . . What I am asking you today is to help me help our students."

Yesterday's training session was the first skirmish in Fairfax County's intensified campaign against drug abuse in schools, a campaign that is 10 years old but, Burkholder said, "has not yet made the difference I have to expect."

In the coming months, Burkholder plans programs for every group of school system employes--principals to substitute teachers to bus drivers--in the hope of halting the spread of the chemical society.

Educators traditionally have spent more time searching for drugs in the parking lots than in the locker rooms. In Fairfax County especially, parents often have pointed with pride to high athletic and academic standards as proof against a drug problem. But according to Burkholder, the school system has to explode both myths.

In the 1960s, the superintendent said, "we were witnessing an evolving life style which involved not only drug use but music, clothes, hairstyles. It became a national stereotype." As he spoke, he faced a crowd of men and women who seemed to embody the other America: tanned, outdoor types in shorts and short hair, Topsiders and Dr. Scholl's and sandals.

"But that stereotype of yesterday may blind us to the drug abuse problems of today," Burkholder continued. Because many students, especially young athletes, don't fit the old hippie image, parents and teachers make the mistake of thinking they don't use drugs.

The problem is intensified by the tendency not to recognize alcohol as a drug.

"Although I am also concerned with the use of marijuana, cocaine, PCP and other dangerous drugs, by far the number-one drug of abuse among students in alcohol," Burkholder repeated. "Augmented by $600 million worth of advertising annually by the liquor industry, the keg party has become an American tradition. It has no place in the high schools."

Concern over teen-age drinking in recent months has resulted in the raising of Virginia's legal drinking age from 18 to 19 and public service announcements on rock radio stations. Earlier this week, Loudoun County school officials announced the purchase of 10 breath analyzers to be distributed to all middle and high schools. Fairfax has 25 simpler kits that detect the presence of alcohol, but not its quantity.

The students who spoke yesterday were culled from a group that was interviewed by the board's ad hoc committee on substance abuse. That committee, directed by deputy superintendent Donald Lacey, is scheduled to make its full report Sept. 1.

In the meantime, Burkholder announced that he will implement a new health curriculum at the elementary and intermediate levels, increase the so-called SARP program (Substance Abuse Resource Person) at each school and experiment with training peer counselors, an idea borrowed from the NFL Players Association, which now trains two members of each NFL team in intervention techniques.

Although Burkholder just brushed the subject, many athletes are sensitive to the increasing use of sports themes in beer advertising.

As school board attorney Thomas J. Cawley urged the coaches to be cautious about using players who may be on drugs--"You can imagine a coach saying, 'Well, he's only had one beer and we have to win the game,' and how inconsequential that would seem in a court of law" if he were injured--one coach nudged his neighbor. "Bring out your best," he said sarcastically.