A tough, highly focused program to raise test scores paid off in a big way last spring at Jefferson Junior High School in Southwest Washington.

In May 1978, ninth graders at the school, like many others around the city, had performed at the sixth grade level on the standardized tests in reading and math.

By last spring, however, Jefferson's ninth graders had shown a dramatic improvement, performing at 10th grade levels and scoring above the national norms in both subjects.

A school-by-school list of the 1980 test scores was issued recently by the D.C. school system.

We wanted to raise those test scores. We worked at it, and we did it," said James A. Campbell, who was principal at Jefferson until last month when he was reassigned to Coolidge Senior High.

There was no complicated formula, Campbell said. It was just a matter of devoting extra time and effort to basic reading and math.

To do this:

All students at Jefferson were required to take one period of reading a day with phonics taught to those who needed it.

About half the students took a course in math fundamentals in addition to their regular math classes.

All students spent two periods a week studying specific topics, such as measurement or synonyms, where Jefferson had tested low. There were homework assignments on these skills almost every night for everyone in the school, as well as special exercises on how to take standardized tests.

To provide class time and teachers, Campbell said, the school cut back on its elective courses in social studies, shop and home economics.

"They can get all the electives they need in high school," he explained.

"Maybe we let some things slip," said Vera White, a former assistant principal who is now Jefferson's acting principal. "But we thought reading and math were the most important and we really concentrated ond the. That's all we were doing."

As in the past, the 1980 report on school test scores shows that academic achievement generally corresponds to the education and income levels of the neighborhoods where children live. But there are an increasing number of exceptions like Jefferson. Virtually all its 560 students come from low-income families living in public housing or low-rent apartments.

The city-wide averages in reading and mathematics rose last spring for the second year in a row, following a decade of declining or stagnant achievement.

The gains were greater in elementary schools than in junior highs, despite the progress at Jefferson. Superintendent Vincent E. Reed said the higher scores were a "payoff" from the school system's new competency-based curriculum, a step-by-step program to teach specific skills.

Of the city's 28 junior high schools, the only one beside Jefferson to top the national norms was Deal, Fort Drive and Nebraska Avenue NW. Ninth graders in the selective math and science program at Ballou Senior High School also scored above the norm.

All of the tests were given in early May to third-, sixth-and ninth-graders throughout the city. The multiple-choice exams, called the Comprehensive Test of Basic Skills, were prepared by the California Testing Bureau, a division of McGraw-Hill Publishers. It took about three hours to complete the tests.