Have criticisms leveled at the Montgomery County school board so hampered members' reelection chances that a new majority will be swept into office in November? Or has the imbroglio over county school closings and racial balance policies been created by a few vociferous parents who will have little overall impact on the election?

These questions confront 15 candidates vying for four open seats on the board in what is probably one of this fall's most unpredictable races.

"It's an awfully hard race to call," said Jane Merriam, president of the Montgomery County Federation of Republican Women.

Part of the reason is that this board has not avoided controversial issues. It voted to close 28 schools by 1984 and to increase the percentage of minority students who must attend a school for it to be considered racially imbalanced. The board set educational policies for its students that some hailed and others panned. Against the advice of its own staff, it vetoed contraception instruction in eighth-grade sex education classes.

In spite of criticism from several organizations, including a majority on the County Council, the board agreed to challenge the Maryland Board of Education in court for the right to close Rosemary Hills Elementary, a school that has been called a symbol of voluntary integration efforts, and to change attendance boundaries of Montgomery Blair High and Eastern Intermediate schools.

The Montgomery body became the first local school board in Maryland history to have its decisions -- on Rosemary Hills, Blair and Eastern -- overturned by the state board of education.

The state board subsequently accepted the county board's interim proposals for the way to keep open Blair, Eastern and Rosemary Hills while the county's court challenge is pending. The state body, however, also said there was no emergency that justified closing Rollingwood and North Chevy Chase elementary schools, which the Montgomery board now plans. The dissenters on the state board accused the county board of showing "an appalling lack" of concern for the communities involved.

At the same time, this board also has reduced class sizes, transferred additional funds from administrative functions to the classroom and bought more textbooks. It also has fought for funds from the county government to increase the number of elementary school teachers and for a seven-period day in the county's high schools.

Obviously, predictions on the race's outcome vary. But several observers feel that incumbents Carol Wallace, a former board president, and Joseph Barse, a Department of Agriculture economist, and the four endorsed by EDPAC, a political action committee, will be among the survivors of the nonpartisan primary that will winnow the field to eight.

The EDPAC candidates are CIA analyst Marilyn Praisner, Equal Employment Opportunity Commission program planner Odessa Shannon, University of Maryland undergraduate dean Robert Shoenberg and Montgomery College professor Jim Cronin.

Others forecast that Zoe Lefkowitz, past president of the Montgomery County Council of PTAs, and physicist Barry Klein, a former instructor at New York and George Mason universities, will complete the field.

Paul Clark, county Republican Party chairman, feels that "conservative Democrats and Republicans will support Barse and Wallace" and that EDPAC, a bipartisan group formed last year, provides better organization than the other challengers and that its four candidates will represent a more liberal alternative to the incumbents.

Clark added that the remaining two primary survivors could come from Barse's slate: Herbert Grossman, an administrative judge with the Nuclear Regulatory Commission, or Montgomery College business law professor Elizabeth Witzgall -- but only if the two are closely tied with Barse and Wallace in the minds of voters.

A ranking member of the county's Democratic party sees the outcome differently, arguing that the atmosphere in the county is "violently anti-incumbent. This county has had it with the current school board." The official said that the EDPAC candidates "are the best financed and have the better organization" and that Klein probably would be the next-strongest candidate.

Other observers aren't so certain. "You may as well get out a dart board," said one person affiliated with the board.

Roscoe Nix, chairman of the county's NAACP chapter, is another EDPAC supporter who believes that its four candidates will do well in the primary, but notes that this doesn't mean they are shoo-ins in the general election. In 1974, Nix came from dead last of the eight primary survivors to win a seat on the board.

Others are waiting for the major endorsements, including those by the school system's own unions. Vincent Foo, president of the Montgomery County Council of Supporting Services Employees, which represents 3,500 school employes, who says he likes Praisner and Klein in the election, but will go no further.

"Right now, I don't know how to read the electorate," said Foo.