Montgomery County School Superintendent Charles M. Bernardo has done the job he was hired to do three years ago, and for some people that is just the problem.

The long-simmering problems Bernardo was hired to solve included declining test scores, almost-new schools that were half empty because of declining student enrollment, and a sleek bureaucracy proud of its accomplishments and jealous of its territory.

As he brought in new management concepts and outside consultants, Barnardo, 40, also stepped on academic toes, punctured administrative egos, and because the focal point of so much criticism that the renewal of his contract became an issue in this year's school board elections.

The contract itself would not have expired until 1979. However, 1st week the board voted to renew the $53,000 annual contract a full 16 months ahead of schedule, an action that surprised a number of observers and underscored the controversy that has followed Bernardo since his arrival.

"Montgomery County is not accustomed to a superintendent making . . . his principal occupation the management of the educational process itself," Bernardo said last week, trying to explain why resistance to his programs remains so strong among the country's 7,000 teachers and administrators.

"The superintendent traditionally has been viewed as a logistical administrator, (giving) beans, bullets, and butter (to teachers). "The locus of power (in educational questions) lay with the bureaucrats," he said.

Both the style and temperament of Bernardo contested striking with those of his predecessor.

Bernardo is a man whose suits never appear wrinkled and who is unflappable almost to the point of stiffness - his only reaction to heated debates at school board meetings usually is to raise or lower his eyebrows. He succeeded Homer O. Elseroad, a gregarious native Marylander who wore bow ties and made a point of asking after the health of his subordinates' wives and children.

Not only were the two men different, so were their ones. Elseroad presided over the school system for 11 years during a period of unprecedented growth. Enrollment hit an all-time high of 126,000 in 1972. New schools were being built around the county.

Shortly afterward, disturbing trends were noticed, which Bernardo ultimately was hired to cope with, according to board member Verna Fletcher. Student test scores began dropping in certain subject areas (although in general. Montgomery's test scores remained above state and national averages). Enrollment began plunging - as it did in school systems across the country. By 1982, only about 95,000 students are expected to be enrolled in the county school system.

As a result, schools that were once clock-a-block with students were now half empty, which means that enormous sums of money were being spent to heat and maintain empty classrooms.

In addition, much of the county's minority student enrollment was concentrated in a few schools, and integration plans had not yet been put into effect, Fletcher said. While innovative teaching programs were encouraged at individual schools the kind of program was not consistently available around the county school system.

Elseroad was on the verge of resigning to take a consulting job in Denver and, "It was time for a change," said Fletcher, who was a member of the 1975 school board that hired Bernardo.

Before he arrived from Providence, R.I., where he had headed a school system one-sixth as large as Montgomery County's, Bernardo sent a team of outside consultants to the area to look things over - the first example of the new superintendent's business-school approach to problems.

When Bernardo himself arrived, he brought with him several key associates from Providence to help reorganize the administration, to restructure the special education program for children with learning disabilities, and to cope with the other long-term problems.

"I was hired to deal with specific problems, and I felt the old organization was inappropriate to meet the needs of things that should have been addressed earlier," Bernardo said in a recent interview.

In the course of this reorganization, bureaucrats with enormous power got shuffled to less powerful posts, though none actually lost a job or suffered a salary decrease. Also, lines of authority were changed, giving Bernardo more direct control over teachers, principal, and area superintendents.

Many teachers, accustomed to a board measure of autonomy, objected to Bernardo's detailed directives on such matters as individual course curriculums.

They also disliked having to compile enormous amounts of statistics on their students' progress. These statistics were a part of what Bernardo called the "accountability of educators toward the children." But teachers complained the forms wasted their time and kept them from their basic mission of teaching.

Additionally, plans were developed and implemented for the closing of 26 neighborhood schools. That created howls of protests from affected parents. Through it all, the system's budget continued to increase: it now stands at $268 million. Money now was allocated only after the new cost-effectiveness studies Bernardo brought with him and had been applied. Administrators now had a much more difficult time justifying their need for revenues than they had had in the past, several of them said.

Bernardo described his approach as a "systems management approach to education, using techniques that could be used in any business for effective administration eof resources."

Bernardo said this approach demanded that teachers determine a child's needs, and fulfill those needs by the end of a set amount of time, usually the school year. The proof of the pudding is that test scores have started to rise again, he said.

Previous administrations had been concerned about "accomodating the staff. This administration is accommodating the needs of children. I have a very great regard for their professionalism (but) the responsibility as to where a school system should go does not rest with them . . . but with the superintendent," Bernardo said.

Many teachers feel that some important intangibles - trust, perhaps, or something they call "professionalism" - has been lost.

"It look a lot of good people 30 years to create something good, and it's been destroyed in three years," complained George E. Kaye, a physical education teacher at Woodlin Elementary School and an official of the Montgomery County Education Association, which represents teachers

"Teachers and administrators had all developed a level of trust with the people they worked with. Teachers have to have a certain level of consistency in routine or 'else they can't teach. Now we're not sure what will happen. Morale has plummeted," said Kaye, whose voice often shock with emotion as he talked.

"Bernardo has taken away professionalism, the right of teachers to make judgements about children," said Edith Blackman, a guidance counselor at Randolph Junior High school.

"He put that authority in committees, even though the entire staff voted against it . . . The school system is buying everything that man is selling," she said.

William L. Bowen, the incoming principal at Poolesville High School, put this perspective on the running conflict between Bernardo and the teachers and administrators who held their jobs before he ever arrived.

"Elseroad was the leader we needed then. He was a fantastic person, wanted to know about the family, how you were feeling. Bernardo is the kind of man we need now, a model administrator to deal with today's problems."

Bowen said many of his collegues "weren't taught anything about systems management in school, they can't handle it. Bernardo says "If you know something about the kid, what are you going to do about it? Show me the data - and the teachers go wild because it creates more work for them. But give them time to learn how to compile the data more efficiently, and you'll see them change, too. Time is such an important component of change," he said.