He has learned to count and do some addition when he was just 2 years old, his mother recalled, while watching "Concentration" on television. He picked up reading a little later, she said, by studying the ads in Reader's Digest.

For Randy Kunkek, now 12-year-old seventh grader at Mark Twain Intermediate School in Springfield, Va., there was another academic landmark Saturday. He walked across a stage at Johns Hopkins University to be honored for scoring 750 on a College Board math exam-a higher mark than that received by 99 percent of the nation's college-bound high school seniors.

"I didn't really know what the [Scholastic Aptitude Test] was about before I took it," Kunkel said yesterday. "It didn't seem all that hard."

At the ceremony in Baltimore two other junior high students from the Washington area were honored for scoring even higher than Kunkel. Ethan Miller, 12, of Western Junior High in Bethesda received an almost perfect 790 on the math exam out of a possible 800 points $. Shino Kakunaga, 13, of Robert Frost Junior High in Rockville, scored 760.

The three were the highest-scoring participants in an unusual mathematics talent search, directed with missionary fervor by Julian C. Stanley, a psychology professor at Johns Hopkins.

When the search started in 1972, it first yielded only 396 students from the Baltimore area.

This year it had 3,632 contestants from five states-Maryland, Virginia, Pennsylvania, Delaware and West Virginia and the District of Columbia. All of the participants were seventh graders or young eighth graders who had skipped a grade. All of them had previously scored in the top 3 percent of national norms on a standardized math test for their grade.

"What we're trying to do is find the highly talented youngsters in math, and to certify, identify and label them," said Stanley, after certificates and books were handed out to about 150 high scorers on Saturday.

"We want to label them for themselves, for their parents and for their schools as being math talented," Stanley continued. "Otherwise, many of their schools would simply ignore them or say they just have pushy parents."

Overall, about 1,000 of the junior high students scored above the national average for high school seniors on at least one part of the College Board exam, which tests verbal and writing ability as well as mathematics.

About 150 scored as high as the top 15 percent of high school seniros.

Of the 780 schools whose students took the tests, the one with most scorers in this very top group-five-was Longfellow Intermediate School in Falls Church, which is part of the Fairfax County public school system.

Washington's Deal Junior High School, Nebraska Avenue and Fort Drive NW., had the second greatest number of high scorers-four-along with Baldi Middle School in Philadelphia.

Five other schools in the Washington area were among only 13 in the whole mid-Atlantic region with three students each in the high-scoring group.

They were National Cathedral School for Girls, a private school in Washington; two Montgomery County junior highs, Leland in Chevy Chase and Frost; and Stephen Foster Intermediate in Fairfax County and Swanson Intermediate in Arlington.

Overall, Montgomery County had 124 students scoring above the average for seniors on at least one part of the College Board test, a far greater number than any other school system participating.

Fairfax County had 51 public school students in this category, Prince George's County 50, Arlington 20, Washington 10 and Alexandria 6. All 10 of the Washington public school students attend Deal. In addition, 48 D.C. private school students scored this high.

"There's a very rich pool of talent in the Washington area," Stanley said, "very rich." But he added: "There's nothing magical about what the schools are doing with it. A lot depends on what enters the school."

Indeed, over the past few years much of Stanley's effort have been aimed at getting very bright students out of the schools as quickly as possible and into college.

So far about 100 students identified by Stanley's talent searches have been admitted to college very young, including one boy who graduated from Brooklyn Colleg in 1977. Another is a 12-year-old sophomore now at Johns Hopkins.

For the very top students in each year's talent search, Johns Hopkins runs special summer classes. They teach two to four years of high school mathematics-through analytic geometry-in just eight five-hour sessions spread over eight weeks. This summer similar classes are being held for the first time in writing, literature and German Civilization for students with high verbal ability.

Stanley said many teachers and school officials have opposed his efforts to identify very bright students and move them ahead quickly.

"They have all sorts of erroneous ideas about acceleration," Stanley said. "There's all sorts of social and emotional cant that this is elitist. . . ."

Tobey Wheelock, a 12-year-old eighth grader who was the highest-scoring student at Deal, said he plans to take the fast-math class this summer. But he is not certain how fast he wants to move academically after that.

"I just don't know," he said. "I think I might be sort of alone if I went to college."

The family backsgrounds of this year's three top math scorers vary considerably. Miller's father is a Harvar-trained economist who also attended New York's Bronx High School of Science. His mother is a graduate of Wellesley College.

Kakunaga came to Rockville from Japan at age 7 when her father, a biochemist, started work at the National Institutes of Health. Her mother is a pharmacologist.

Kunkel was adopted as an infant. His father is an airline ticket agent, and his mother fomerly held a clerical job. Neither graduated from college.

In interviews, the high scorers seem unimpressed by their precociousness and the honors it brings.

Miller, who had the top score in math, did not attend Saturday's awards ceremony. He said that he had to go Jewish Sabbath services at his synagogue. Last year, when he scored 670 on the math test, Miller also didn't attend the ceremony even though it was held on a Sunday.

"I thought it would be kind of boring," he said. CAPTION: Picture 1, ETHAN MILLER . . . an almost-perfect 790; Picture 2, SHINO KAKUNAGA . . . runnerup with 760 score; Picture 3, RANDALL L. KUNKEL . . . 750 not "all that hard"; Picture 4, TOBEY WHEELOCK . . . highest scorer from District