Robert Jarvis was frantic. Loudoun County Public Schools were ready to open, and he was still short of teachers.

"I did some quick telephone work," said Jarvis, deputy superintendent in charge of hiring for the rural school system. "I called colleges everywhere, trying to work some magic."

Jarvis called it "pure luck" that he found enough teachers to fill the vacant jobs for this school year. He said he's afraid the school system might not be so lucky next year.

Schools throughout Virginia had to scramble to find enough teachers to run their classrooms this year. Although school administrators have wrestled with teacher shortages in mathematics, science and special education for the past several years, this was the first year many of them discovered a new, more alarming, trend: trouble filling jobs in the previously glutted areas of social studies, English and elementary education.

The problem in finding teachers stems from many sources, but most educators agree that fewer students choosing to pursue a teaching career is at the root of the problem. The situation has become even more serious in recent years because, after graduation, fewer of those prospective teachers actually are taking teaching jobs.

"We're literally on the verge of a desperate teacher shortage," said Mark Spikell, dean of the college of education at George Mason University.

"The supply of teachers available to hire is not sufficient to meet current demand in particular fields," the State Council of Higher Education concluded last month in reporting the results of a survey of 133 of the 141 school systems in Virginia.

Nationwide, the number of new teachers graduated in the past decade has dropped from 36 to 21 percent of all college graduates.

Although the shortages have hit rural counties in Virginia hardest, the problems are creeping into the suburban counties of Northern Virginia as well, where school systems previously had little trouble attracting teachers because of salary scales that are higher than those in most other areas of the state. The school systems' location in the Washington metropolitan area has given them a larger pool of available teachers and has been a strong drawing card for attracting new teachers, according to local educators.

For the first time in recent decades, school administrators in Fairfax County have asked the school board to approve a special $15,000 recruitment fund to lure teachers in hard-to-fill subject areas into the school system. Teachers in such fields as Russian language or special education would be given one-time $500 bonuses to join the school system, said school administrators.

Almost half of the school divisions in the state surveyed by the Council of Higher Education said they were having extreme difficulty finding mathematics teachers and instructors for children with learning disabilities. More than one-third of the local systems polled were having problems finding teachers for earth science and for emotionally disturbed children.

About one of every four school systems said it was having extreme difficulty finding qualified teachers for chemistry, physics, hearing and speech disorders and industrial arts.

Arlington, Alexandria and Fairfax school systems all reported problems finding science, special education and vocational education teachers this year. Arlington had additional trouble filling elementary music, foreign language and math positions, and Alexandria school administrators said they also had difficulty finding journalism teachers.

Fairfax County started this school year short 13 teachers: eight vacancies for teachers in the field of learning disabilities and other openings for industrial arts and earth science teachers as well as for teachers of handicapped children, according to James Shinn, director of employment services for the schools. The system managed to fill the holes in its staff by the third week of classes, he said.

"We have a major crisis," said Walt Mika, president of the Virginia Educators Association. And he predicted that the shortages will become even more critical.

"I can count on one hand the number of students we will be graduating as secondary math teachers," said Spikell. "The prospects look bleaker as every year goes by."

Many school systems have plugged the gaps in their staffs with instructors who are teaching outside the fields in which they have been trained, called "unendorsed" teachers in education jargon.

Almost one-half of the earth science teachers in the state are unendorsed, despite six-year-old regulations that all earth science teachers be endorsed by the 1982-83 school year, the Council of Higher Education survey showed. Regulations imposed by the State Board of Education in 1976 required teachers of earth science, one of the most popular science courses in Virginia high schools, to receive training in that specific field. Previously, the teachers needed training only in general science and were not required to have training in geology, oceanography, astronomy or meteorology, the areas covered in the earth science course.

"The 'science lobby' was wrong when it brought about the change in the earth-science endorsement," complained one school superintendent. "The colleges simply are not preparing enough endorsed teachers."

About 17 percent of the state's special education teachers are not fully trained in their teaching areas, 12 percent of the trades and industrial arts instructors are unendorsed and 7 percent of the state's chemistry teachers haven't met full qualifications, the poll of superintendents showed.

Administrators in all Northern Virginia school systems said that, in most cases, they have been able to avoid using teachers in classes outside their fields of specialization. The occasional "unendorsed" teacher who is hired is usually only a few college course hours away from receiving full endorsement, they said.

"Special education continues to be the most difficult area," complained another superintendent who responded to the Council of Higher Education survey. "We are experiencing increasing difficulty in finding English, social studies and foreign language teachers. It is most impossible to find teachers endorsed to teach data processing."

All Northern Virginia school districts said they have recorded substantial declines in applications during the last four years. Loudoun and Fauquier counties reported that applications have plunged 50 percent in the last four years.

"In the last year, applications for elementary teachers dropped off 30 percent," said Jarvis of Loudoun County schools. He said school officials traditionally had faced a flood of applicants for the elementary school teaching jobs.

The Fauquier school system queried 38 colleges in search of one person to teach children with learning disabilities, said James Brumfield, assistant superintendent of schools.

"One or two applications floated in," Brumfield said.

Most education officials blame the shortages on two major factors: the declining number of students entering college education programs and a significant decrease in the number of education school graduates who enter the teaching profession.

They say the decline in students pursuing careers in teaching is becoming an even greater factor in teacher shortages than the number of teachers leaving the classrooms to take higher-paying jobs or to escape the mounting discipline problems plaguing many schools.

"We're going to face teacher shortages in every area for the next decade," said Julius Roberson, dean of education at James Madison University in Harrisonburg, which has one of the largest teacher colleges in the state. "Superintendents are telling us we're not graduating enough students."

The number of students graduating from Virginia's 33 state-approved college education programs has fallen 25 percent in the the last four years, according to the state Council of Higher Education. Although college enrollments overall have dropped during the past few years, the decline in education graduates has been disproportionately high, say college officials.

Roberson and other college officials say the low salaries paid to teachers is one of the primary reasons that students are shying away from teaching careers.

"They don't see the nonfinancial rewards as all that great either," said Roberson. "Teaching has reached a point of low esteem from the general society's point of view."

But one of the overriding deterrents to teaching careers was the teacher surplus of the last decade, Roberson said.

"People have known for a while now that there has been a surplus of teachers," said Roberson. "We're now reaching a point that we can see the trends reversing."

It could take another decade, he said, to change enrollment directions again and overcome the shortage.

About half of the 2,500 students who graduated from Virginia colleges with teaching degrees last year never entered a Virginia classroom as a teacher, the Council of Higher Education report showed, but opted instead to take jobs in other states or go into different professions.

The number of graduates turning to private business is even greater, college officials said, among prospective teachers of math, science, business, computers and industrial arts.

"The students think that if you're going to take a lot of math and science, why not go to work for industry where the financial rewards are more tangible," said George Mason's Spikell.

In attempts to combat the teacher shortages, state education agencies and teacher organizations have stepped up lobbying efforts in the state General Assembly for increasing teacher pay. The General Assembly establishes a base salary for teachers, with local school systems supplementing the pay scale.

And college officials said they plan to do more high school recruiting in an attempt to lure more students into education colleges.

Reports from the Council of Higher Education note that although declining student enrollments may be averting immediate critical teacher shortages, researchers have warned educators that enrollments will begin to increase in the mid 1980s, adding to school systems' already growing headaches.