One of the first tests for Norman H. Saunders, newly elected Prince George's County school board chairman, will come tonight when he and other board members consider a controversial proposal to reorganize busing in the country.

The proposal, which will affect 11,000 children who are now bused, is designed to dramatically increase the number of elementary school students attending schools in their own neighborhoods and reduce the number of schools with majority black enrollments.

The proposal not only would provide a statistical nightmare resulting from the proposed closure of 11 elementary schools, but would provide a unique challenge to a 1973 court order, which mandated desegregation of the school system.

School officials say the desegregation plan in the system has not been able to keep up with demographic changes that have resulted in changes in the racial make-up throughout the system.

Now, school officials say, instead of schools that are racially segregated by policy, there are a number of schools that have become all black as the result of natural population migrations.

The newly elected school board chairman also is negotiating, along with the school board, a new contract for the 8,000 teachers in the district. A decision on the contract is due by the end of the month.

The school board also will face tough decisions this year when budget hearings come up. Since this is an election year, some politicians may be prompted to be extra tight with county funds.

And if these issues arean't enough, the board has to continue its pledge, through policies and programs, to improve basic reading and math skills of students in the system, which currently ranks below the statte average in some grades.

The election of Saunders Dec. 5 reaffirmed the fact that school board members generally are pleased that there is not the divisiveness that once ruled the board.

Saunders's election, along with the re-election of Mrs. Susan Bieniasz as vice president, maintains the moderate slant the board has taken since the last school board election, according to board members, who praised Saunders's even-handed control of the board.

"It is going to be a good board - not flamboyant," said Mrs. Bieniasz.

Mrs. Maureen Steinecke, who had announced that she would seek the chairmanship but was not able to get enough votes, said she was happy with Saunders's election.

"It will continue to be a more moderate school board than in the past," said Steinecke, who added that there was more agreement on the school board now than in the past.

The present board has taken a dramatic shift in its decision making process since the 1976 election, which eliminated two conservative members.

The present board deals with issues and not with personalities, according to board members, who now pride themselves on the "constructive direction" the board is taking.

After Saunders was elected, he told one audience he planned in the near future to submit a set of objectives to the school board.