Washington area school officials are looking for a couple of thousand good teachers.

Educators in Arlington, Fairfax, Montgomery and Prince George's counties and in Alexandria and the District estimate they will need to hire about 2,000 new teachers for the 1985-86 school year -- a surprising number for schools that five years ago faced teacher surpluses in some areas.

Prince George's County alone anticipates recruiting 400 to 500 teachers for next year, after laying off 500 teachers only three years ago.

In Arlington, school officials began to recruit teachers last year after a decade of not doing so; some larger districts, such as Fairfax and Montgomery, never stopped recruiting, but they have intensified their efforts in the past several years.

This year, say school officials all over the Washington area, they will be starting earlier, looking farther and spending more money than at any time in the past decade to attract the "best and brightest" teachers to their systems.

The new recruitment effort is another swing in the pendulum of demand for teachers, nationally as well as locally, that has been going back and forth for the past 15 years. William Barrett, staffing specialist for Montgomery County schools, recalls how different it was in 1970, when he first began personnel work. "We hired 1,300 teachers. We were opening schools. Everything was grow, grow, grow," he said.

Then dipping enrollments and school closings drove the number of new hires each year to 100 in the mid-1970s and to as few as 60 five years ago.

Recently, "we have been seeing the need to go back upward," Barrett said. "With the expected enrollment climb, we could be hiring in the neighborhood of 500, 600, 700 teachers for the next school year. From my perspective, it's a little bit scary."

The teachers are needed, officials say, to replace retirees as well as young teachers who are abandoning the profession. In addition, more teachers are required in some school districts to meet policy decisions, such as smaller class size or stiffer graduation requirements that have spawned the need for new classes.

Nationally, large numbers of retiring teachers, a shrinking pool of teaching graduates and slightly rising school enrollments in some areas may combine to create a teacher shortage in the nation within 10 to 20 years, education studies show. As a result, school districts across the country will have to recruit more vigorously.

"Placement officers are seeing an increase in the numbers of recruiters coming on campus. . . . It's amazing," said Janet Kerstein, executive director of the Association for School, College and University Staffing, an 800-member group of education placement officers.

After a decade of not searching actively to fill teaching vacancies, Arlington began recruiting again in 1983. Factors Arlington school officials cite as reasons for the recruiting resurgence are affirmative action efforts, leveling enrollments and the retirements of a large group of older teachers hired during school expansions in the late 1950s.

"About 30 percent of our teachers are going to be eligible for retirement in the next five years; we have to go out and replace them," said Lilla Wise, assistant personnel director for Arlington schools, which are seeking about 100 teachers for next year.

Maria Combos, who graduated in May from Longwood College in Farmville, Va., is one of the newest recruits in Arlington schools. The 22-year-old Spanish teacher said she had heard dire predictions of a teacher surplus and was surprised to receive between 20 and 30 calls from interested school districts after she graduated.

Stacy Woods, with a degree in math from Virginia Commonwealth University, found herself in a much sought-after category of teachers. "I got a lot of job offers from people I didn't even apply to," said Woods, 24, who was attracted by Arlington last year.

Science, math and language teachers are those most in demand.

"I think Arlington is to some degree a microcosm of what's going to happen," said Lyle Hamilton, communications manager for the National Education Association (NEA). "We're going to have an inordinate need for teachers. You're going to see the beginning of a teacher shortage. The question is, where are these teachers going to come from?"

District school officials plan to launch a $25,000 recruiting drive in the spring, using advertisements in professional journals, visits to colleges around the country and videotapes promoting the school system to attract at least 300 new teachers, said spokeswoman Janis Cromer.

In Fairfax, where at least 600 new teachers are needed, this year's budget for teacher recruitment is $10,000 -- two and a half times the amount spent to search for teachers four years ago. The Alexandria schools are looking for about 55 new teachers.

Several recent studies, such as the Rand Corporation's "Beyond the Commission Reports: The Coming Crisis in Teaching," as well as statistics gathered by the National Education Association and others, explain what many school districts are seeing.

Children in the baby "boomlet" -- the offspring of the post-World War II baby boom generation -- are growing up and filling elementary school classes that had been shrinking since 1970, the Rand report says.

Because older, more experienced teachers were the least likely to lose their jobs when layoffs were frequent, many school systems now have a large number of teachers over 50 who will retire in the next decade.

Elizabeth Dalton, 63, is one of Arlington's most recent retirees. When she joined the school system in 1942 at a salary of $1,240 a year, teachers "just appeared on the job" with little or no in-service training and faced packed classrooms all day. "I tried to teach a class in a hall; I couldn't even see the whole class," Dalton recalled.

Many teachers hired during those growing, crowded decades are nearing retirement age. According to NEA figures, 15.5 percent of the nation's teachers were age 50 or older in 1976. By 1981, 19.4 percent were in that age group.

At the same time, fewer students are graduating with degrees in education, and many of those who do are spurning the low-paying field for more lucrative jobs in the private sector.

Linda Darling-Hammond, author of the Rand report, said that as career opportunities in other fields -- particularly for women and minorities -- have expanded, teaching has lost appeal.

"Teaching has relied on a sort of captive labor force in the past," and in recent years "there has been a massive shift in career choices of minorities and women, particularly the most academically able, who once chose teaching," she said. "That, I think, is not going to change."

Robert Cudney, assistant superintendent for personnel in a suburban high school district 25 miles from Chicago, has seen the change in career choices shrink his pool of teacher applicants. He said the number of applications he receives dropped from as many as 5,000 a year through the 1970s to 1,500 last year.

Besides the invisible hand of demographic change, internal tinkering with class sizes and academic requirements is helping engineer the need for more teachers.

In Goose Creek Consolidated Independent School District, an area 20 miles southeast of Houston, a new lid on class sizes for the early elementary grades and a required prekindergarten for 4-year-olds who cannot speak English will boost the demand for teachers and force the system to recruit out-of-state teachers next year, school officials said.

The same thing is happening in Prince George's County, where the superintendent's request to reduce class sizes by one next year will create spots for 125 new teachers, according to Carl McMillen, director of professional personnel.

In Virginia, stiffer graduation requirements in math, science and foreign languages adopted by the State Board of Education in 1983 have increased the need for teachers in those areas.

The simultaneous demand for teachers in area schools has created some friendly competition among local districts, according to some school officials.

"It's rather good-natur- ed. . . . We compare notes; there is a lot of joking and jostling about it," said Montgomery County's Barrett.

"We're all looking for the same applicants. We want that top 1 to 2 percent," agreed James Shinn, director of employe services for Fairfax County schools. Officials say they cannot lure applicants with dollars because salary schedules are fixed in advance. But they can search farther out of the metropolitan area, make more visits to more colleges and hurry to offer contracts before the district next door does so.

Some education researchers say that despite the best recruiting efforts, more people will become teachers only if the profession is somehow made more attractive.

William Graybeal, research specialist for the NEA, said a future teacher shortage depends on "our ability to attract and hold the kinds of people we really need. If we don't do something about the attractiveness of teaching . . . it makes sense that we're not going to be able to be as selective as we are now."