Prince George's County School Superintendent John A. Murphy, terming the first year of the county's four-year magnet school desegregation plan a success, announced yesterday he is seeking to accelerate the plan with the creation of 16 new magnet schools by September.

Murphy's proposal would speed up the desegregation plan by one year, creating a total of 20 new magnet schools by the 1987-88 school year. It would increase funding to 10 predominately black schools next year. Five schools would close in September under the plan, and two would close the following year.

Murphy, unveiling his proposal at a special meeting of the Board of Education yesterday, said he wants to step up implementation of the plan because magnet schools have worked well.

Eight of the 12 magnet schools created this year have achieved one of the primary goals of the desegregation plan: The number of minority students at those schools has fallen to below 80 percent, according to a school spokesman.

The magnet programs "were an unknown quantity a year ago," Murphy said. "But now we feel we can go ahead and deliver . . . . I think delaying would serve no practical purpose for implementing the plan."

Murphy said he also made the decision to move ahead so that all parents with children in the school system can benefit from the programs.

"Parents have a right to know now what magnets will be where rather than making them wait three or four years," he said.

School officials, under court order to desegregate the school system, began implementing a magnet program in September to achieve racial balance by offering special programs to attract white students to schools with large black enrollments.

Part of the plan involves the creation of compensatory education schools -- predominately black schools that receive extra money for teachers, books and other supplies.

The school system began by setting up 12 magnet schools and 10 compensatory education schools. The NAACP, which sued the school system over the issue of desegregation, has agreed to the plan, approved last June by a judge.

Next year, new magnet programs would be started in science and mathematics, Montessori instruction, a classical academy with a strong basic skills curriculum and an emphasis on discipline, foreign language immersion, humanities and social sciences, creative arts and a center for the visual and performing arts. One magnet high school would offer a college preparatory program.

Murphy said the accelerated plan can be accomplished with the $12.9 million that County Executive Parris Glendening has promised to set aside for magnet schools next year.

Some school board members said they have reservations about Murphy's plan, but several black leaders said yesterday they favor the accelerated schedule.

"The timing is right," said James Garrett, a member of the Committee of 100, a citizens advisory group that has been studying the magnet school plan. Garrett said waiting four or five years would hurt the desegregation effort because by then many more whites may have moved out of the county.

"If we desegregate we have to have someone to desegregate with," he said.

"The sooner the better," said John R. Rosser Jr., a member of the NAACP and one of the plaintiffs in the suit. "I like the idea of implementing the plan more rapidly, but as far as closing schools goes, I'd like to see what the impact is."

School board Chairman Paul R. Shelby said of Murphy's plan: "I like it very much. The thing we always have to keep in mind is that we are under court order to desegregate and if we don't do it voluntarily it will come down to a mandatory busing plan."

But several other board members said they had reservations.

"I think there are some wonderful things in it, but there is lots and lots of room for refinement and clarification," said board member Lesley Kreimer. She said the school system should study the proposals for a year before implementing them.

Board member Sarah Johnson agreed with Kreimer that the proposal is "too much, too soon . . . ."

Board members have scheduled public hearings on the plan for Feb. 19 and 26 and March 4. Final action is expected by March 6.

Murphy said the board must act quickly so that the programs can be advertised and established in time for the next school year.

When Murphy's plan is complete, 32 of 175 schools in the county would be magnet schools and another 15 would be compensatory education schools. Five other schools would be interim compensatory education schools, meaning they could someday be converted into magnet schools or officials could desegregate them in some other way