The District of Columbia Board of Education last night approved wide-ranging rules against discrimination in interscholastic sports, including a provision that would permit girls to try out for football and wrestling teams unless separate girls' leagues in those sports are established.

The new rules, which also ban discrimination on sports teams based on personal appearance and "sexual orientation," including homosexuality, will go into effect next fall.

In separate action, the board also voted to permit high school sophomeres to transfer to any senior high in the city, starting in September 1980.

Students still would be assigned according to the geographical boundaries established in 1968 aftter Judgr J. Skelly Wright's desegregation decree. But, under the new policy, transfers would be granted for any reason as long as no school becomes overcrowded.

Board members said they adopted the liberal transfer policy in response to widespread complaints about current rules, which allow out-of-zone transfers only in cases of hardship or because specific courses are unavailable in assigned schools.

The liberal policy will remain in effect for two years, as a trial to see what effects it has, the board said.

In adopting its new rules on athletics, the Washington school board went considerably beyond U.S. regulations against sex discrimination in sports, known as Title 9, which allow school systems to have terms for boys only in contract sports.

However, since 1977, Maryland has allowed girls to try out for boy's teams in all sports in which no separate girl's team are operating.

Last fall a girl played on the junior varsity football team at Poolesville and took part in one varsity game at the end of the season.

School sports leagues in Virginia have gone no further than the U.S. antidiscrimination rules. Last month, in the first break from the tradition of separate teams in all major sports, the Fairfax County School Board voted to allow a girl to try out for the baseball team at McLean High School.

"This school board really is very serious about giving the girls an equal break," said D.C. board member Alaire B. Rieffel, who introduced the rule change last night.

"If you don't have a girls' football team, you have to let them try out for the [boys'] football team," she explained. "I don't care for football myself, but if we are going to have it for boys, then you have to let girls have it, too, or let them try out for the same teams with boys."

The new rules for both sports and high school transfers were passed by the board unanimously with almost no discussion. Rieffel said there had been studies made of both subjects and extensive debate in board committees since last fall.

The rules permit separate teams for boys and girls in any competitive sports provided that both sexes actually have teams of their own. Thus, playing arrangements in basketball, which has both boys' and girls' leagues, can remain unchanged.

Besides sex, the ban on sports discrimination also applies to "handicapped condition, race, color, religion, citizenship status, national origin, marital status, personal appearance, and sexual orientation."

In addition, the new sports rules allow athletes to challenge their coaches' decisions through an elaborate grievance procedure that includes formal hearings with cross-examination.

Officals said they had no idea how many students would ask to switch to out-of-zone high schools under the new transfer policy. But they said that Wilson and McKinley high schools, which might be the most popular because they have strong academic reputations, probably would not be able to take many newcomers because they already are near capacity.

Before Wright's 1967 decree, the D.C. school system had several "optional zones," which the judge said allowed white students to switch out of heavily black high schools. This year every high school except Wilson is more than 99 percent black. At Wilson-at Nebraska Avenue and Chesapeake Street NW-blacks make up about two-thirds of the student body.