Barbara F. Martin was unanimously elected chairman of the Prince George's County Board of Education last night and pledged to address concerns about access to magnet schools, try to improve minority staffing and seek funds for building improvements.

Martin, 65, who served this year as vice chairman, was first elected to the nine-member board in 1984 after teaching for 30 years in county elementary schools.

Doris Eugene was chosen vice chairman. She first was appointed to the board in 1978 and has since served as chairman and twice as vice chairman.

Martin represents District 6, which includes the Seat Pleasant and Landover areas. A native of the county, she is an active member of the county NAACP Executive Board.

Both Martin and Eugene, a Beltsville resident, will serve one-year terms.

In an unrelated matter, school authorities reported at last night's board meeting that the number of suspensions have begun to decline. During the first two months of the school year, the number of suspensions issued fell to 2,118 from 2,843 in the same period last year.

The county has been developing alternatives to suspensions after a recent report showed the county put pupils out of school at a rate twice that of other large school districts. Superintendent John A. Murphy said the figures did not represent a lowering of discipline standards but rather new ways of handling problem students.