The Alexandria school system will welcome three new principals this fall to head George Washington Junior High, and Mount Vernon and Jefferson-Houston elementary schools.

They will succeed three of the system's most popular and senior administrators, who have a combined tenure of 88 years with the city's schools.

On July 1, Robert F. Yeager, 44, will take over as head of George Washington Junior High; Cecelia Krill, 42, will become principal at Jefferson-Houston Elementary; and Phyllis Bushell-Past, 45, will head Mount Vernon Elementary.

Yeager and Krill worked previously for the Alexandria schools, and Bushell-Past comes from Owensboro, Ky., where she has been vice principal of a middle school for the past year. All three were appointed by the board in the last month.

"I'm very impressed with the qualifications of all three of them," said Timothy Elliott, chairman of the Alexandria School Board. "They all bring unique assets to the job and they will all make great principals."

Yeager will be paid $55,380 a year, Bushell-Past will get $48,880, and Krill, $45,240.

Of the three, Yeager has the most experience in Alexandria schools. He has worked in the system since 1965, including tenures as associate principal of the city's only high school, T.C. Williams, and as associate principal of Francis C. Hammond Junior High School.

"I read a long time ago that you don't make change just to make change," Yeager said when asked about his plans as principal of George Washington Junior High. He will succeed Steve Osisek, who is retiring after 35 years with the city's schools.

"It's obviously going to be a challenge," Yeager said. "Mr. Osisek has been an outstanding administrator."

Yeager and Osisek differ on at least one aspect of education. When asked what the best and worst trends in education have been in the last 20 years, Osisek said the back-to-basics movement was the best trend, while Yeager felt back-to-basics was the worst because "having so many required courses eliminates time for fine arts and elective courses that are important to developing a well-rounded individual."

Krill succeeds Christine Howard as principal of Jefferson-Houston Elementary School.

Krill, who has a doctorate in educational administration from the University of Wisconsin and who taught in Alexandria from 1966 to 1973, said: "The main challenge is going to be getting parents involved since so many students come from the western side of Alexandria. It's hard for the parents to drive clear across town for school functions."

Krill has been an assistant principal in training for the Arlington schools for the last year and favors technological innovations in teaching, such as the computer lab and the computerized writing-to-read program at Jefferson-Houston.

Bushell-Past will succeed Walter Krug, who has headed Mount Vernon Elementary for seven years.

"My goals are to have a high level of parent involvement and community awareness for the educational programs," Bushell-Past said. She has worked for school systems in New York, Wyoming and Kentucky.