Three Alexandria School Board members and three challengers are vying for three School Board seats. The City Council is scheduled to select the new board members on Tuesday.

The three incumbents, Eugene Lange, Judith Seltz and Nelson Greene Jr., have each served one three-year term on the School Board. Each year, three seats of the nine-member board expire. Members seeking reappointment must follow the same application procedure as other candidates.

The three new candidates are Ruth Chamowitz, 38, a a lawyer who worked as a psychologist in the Alexandria schools for six years; Jean Swersky, 49, an artist and designer who has served on five parent-teacher associations in Alexandria; and Elizabeth Walker, a 31-year-old lawyer who was appointed to the governing board of George Mason University by then-Gov. Charles S. Robb.

Lange is the only Republican candidate; the others are Democrats.

The Alexandria school system, which has about 10,000 students, has experienced steadily declining enrollments for a decade.

The School Board is in the process of selecting a superintendent to succeed Robert W. Peebles when he retires June 30.

The board faces several controversial issues, including a recommendation by Alexandria Mayor James P. Moran Jr. to open a health clinic that would dispense birth control devices to students at the city's only public high school, T.C. Williams. That proposal was recently studied by a 39-member task force. There were 365 reported pregnancies among the city's teen-agers in 1985.

The need for higher teacher salaries to keep Alexandria teachers competitive with nearby jurisdictions also has been a hot topic.

Peebles proposed raising salaries 9.8 percent in 1987-88, which the council approved, and raising the salaries by 8 percent in each of the following two years, which the council has not approved.

"The two most important issues facing the board are getting a new superintendent and declines and shifts in enrollment," said Greene, 44, who is vice president and manager of Greene Funeral Home, and president of the Virginia Morticians Association.

Greene, the son of two teachers, said he strongly supports higher pay for teachers. "I think teachers have been underpaid for 200 years."

Lange, a 39-year-old corporate lawyer, said "perceived stability" and declining enrollments are among the greatest tasks facing the board.

"I think the school system is very stable, but we are replacing a superintendent and we have three new {school} principals coming in and what we need is a very smooth transition," he said. Lange voted for the teachers' pay raise.

Seltz, a lawyer with a master's degree in education from Harvard University, said the board's biggest obstacle in the next year will be "dealing with budget constraints." Seltz favors a school health clinic that would dispense birth control devices, and she backed the teacher pay raise as "absolutely essential."

"The primary issue of the board is dealing with the achievement of the very divergent ends of the achievement spectrum," said Chamowitz. She urged continued emphasis on the minority achievement program and restructuring the program for the gifted and talented.

Chamowitz supports higher teacher pay and a school health clinic that would dispense birth control devices with parental consent.

Swersky also supports higher teacher pay, and strongly supports a school health clinic, but not one that would dispense birth control devices. She is a member of the city's health clinic task force.

Swersky said the most important issues facing the board are declining enrollment and the dropout rate.

Walker said the budget is always the most important task of the School Board. In an interview she refused to comment on teacher pay or the proposed health clinic, saying she wanted to study the issues more.