Montgomery County schools Superintendent Edward Andrews announced yesterday he has changed his mind about Takoma Park Junior High School and will recommend that the popular school, more than 20 years old, be kept open for two more years.

"I hail it as a good decision," said an ebullient mayor, Sammie Abbott, who led a costly fight to keep the school open. "We're not going to give up the fight to keep the school open permanently, but it would be fair to say that today we have won."

The school was scheduled to close at the end of this school year. Andrews said yesterday he changed his mind after seeing new census data that showed increased enrollment projections for that area in the coming years. If Takoma Park closed, other schools would suffer from overcrowding, he said.

At the same time, Andrews proposed other changes that include delaying by one year the closing of a senior high school and decreasing the percentage of minority students at two elementary schools.

Takoma Park residents say the postponement is a first step toward stability. "Up until now the door was shut but it did not have a lock on it," said Edward Clements, the school principal. "Now the door has been opened again."

Takoma Park is a mixed community of low- and middle-income residents that straddles the border of Montgomery and Prince George's counties, with most of the population living in Montgomery. Residents on the Montgomery side boast that the junior high, with 370 students, is the centerpiece of their integrated community: Forty-one percent of the students are black, 16 percent Hispanic, a little over 9 percent Asian, the rest white.

The school is a model for what others are trying to achieve, residents argued before the Maryland Board of Education when they appealed the school board's December decision to close the school. When they lost that appeal, they sued in District Court. The City Council earmarked $5,000 for the legal costs and a folk festival netted more than $4,000.

City activists have met continuously with both school and county officials, preparing graphs and analyzing new demographic information, and two weeks ago packed the town hall once again to plead with Andrews to save their school.

At that particular meeting, parent after parent rose to tell Andrews that they had moved to the area specifically because their minority children would feel more at home in a setting such as Takoma Park.

Students at Takoma Park Junior High yesterday echoed those sentiments.

"I'm thrilled," said 14-year old Stephen Taylor, an eighth grader and president of the student body. "I want to go here forever . . . . When some of the kids visit other schools for student government meetings they come back and say, 'Gee, there are no black kids there.' I've got to explain the whole world is not like it is here."

Andrews also recommended yesterday transferring some white students from the Highland View Elementary School in Silver Spring to Takoma Park for their junior high years, bringing the number of students at Takoma Park to about 600. He also suggested transferring students from Rolling Terrace Elementary, a school with a large minority population that presently sends students to Takoma Park, to Eastern Intermediate. That move would reduce minority enrollment at Takoma Park to 53.5 percent, he said.

Andrews also recommended delaying the closing of Northwood High School in Silver Spring until June 1985 and slightly reducing minority enrollments at East Silver Spring and Piney Branch elementaries by transferring some students. The school board is expected to discuss his recommendations with the public at Piney Branch Elementary tonight at 8 p.m. and vote on them March 2.