A story in yesterday's editions of The Washington Post incorrectly reported that 36 states have adopted requirements that high school seniors pass minimum competency tests in order to graduate. Fourteen states have adopted miinimum competency test for graduation, while 36 states require competency testing at some level between kindergarden and high school graduation.

A large number of Arlington's ninth grade students have failed new pilot tests designed to measure minimal skills in such basic subject areas as math, reading, writing and social studies.

Although school superintendent Larry Cuban refused to release or discuss results of the tests, which were given to the 1,410 ninth graders in February, these results were confirmed in interviews with school board members and reprinted in a junior high school newsletter for parents:

43 percent of the students failed the writing sample. In a sample test, students were asked to write a clear, five-sentence paragraph on their favorite television program.

37 percent failed the social studies test. A question on a sample test asked students to pick a "widely recognized civil rights leader from the 1950s and 1960s" from among Martin Luther King, Booker T. Washington, Frederick Douglas and George Washington Carver.

34 percent failed objective writing, in which students had to identify misspellings and errors in grammar and punctuation.

30 percent failed computation, in which students were asked on a sample test to figure sales tax charges and balance a checkbook.

28 percent failed reading. A sample test asked students to answer questions about a classified advertisement in a newspaper.

11 percent failed speech. A sample test asked students to stimulate the reporting of an emergency to police.

Arlington school Board Chairman Thomas L. Penn said he was alarmed by the results of the tests, the first to be given in a four-year program to requre all Virginia high school graduates in 1981 to pass tests like these to demonstrate minimum competencies before being allowed to graduate.

"This is definitely a signal to look further," said Penn. "I am concerned. I want to determine the reason for the results. We're going to take a comprehensive look at the situation."

Virginia is one of 36 states including Maryland, which have decided to require minimum competency tests for high school graduates. According to assistant state superintendent of education Richard Boyer, all 10th graders in the state will be given a standardized test next fall to measure their skills in math and reading. Social studies and writing skills probably will be added to the competency requirements in the mid 1980s, according to Boyer.

Boyer said that Arlington is one of the first jurisdictions in the state and the first in Northern Virginia to administer a locally prepared test. Until the state Board of Education decided last March to administer a single statewide test, school systems like Arlington were planning to give students locally prepared test of varying difficulty.

"I'm surprised at the failure rate," said Arlington School Board member Richard A. Barton who, along with the rest of the board officially will receive the test results and an evaluation of them from Cuban on June 1.

"I certainly wouldn't want to have a failure rate as high as that," said Barton. "Traditionally, Arlington kids score very high (on standardized tests). It sounds suspiciously like there's something wrong with the test design."

Ninth graders and the principals of Arlington's seven junior high schools received the test results in late March, according to several principals.

"There were no surprises," said Joseph Macekura, principal of Thomas Jefferson Junior High School, one of the largest junior high schools in the county. Macekura said students who failed any of the tests were given remedial help and advised of the option of attending summer school.

"The value of the test is to give each school an indication of what's happening, whether we're teaching what we should be," Macekura added. He added that failing students would be given several chances each year to retake the test before they have to pass it to graduate in 1981.

School board vice chairman Mary Margaret Whipple labelled the results "a respectable showing. If everybody passed it," she said, "the test would be too easy." Beginning next fall, she added, every secondary school in Arlington will contain a remedial skills center where students can get help in passing the tests.

"One of the big things," said Whipple, "will be what you do with the students who, despite all the help, still doesn't pass the test."

In response to substantial parental demand Arlington will also open a traditional elementary school next fall, which will stress basic methods of instructions, including self-contained classrooms and textbook instruction.