WHITE PLAINS, N.Y. (AP) _ A school district must supply a sign-language interpreter for deaf parents at school-sponsored conferences involving the education of their children, a federal judge ruled Wednesday.

''School-sponsored activities that are designed for parental involvement and are focused on the student's academic or disciplinary progress ... must be made available to the hearing-impaired,'' U.S. District Judge Gerard Goettel wrote.

The case is the first of its kind in the country, said Marc Charmatz, attorney for the National Association for the Deaf Legal Defense Fund, which brought the case. He said most school districts willingly supply sign language interpreters.

The parents, Kenneth and Karen Rothschild, have two children who can hear normally in the Ramapo Central School District, Charmatz said. One is a fourth-grader and one a high school senior. The district is in Rockland County, north and across the Hudson River from New York City.

Since the early 1980s, the parents have sought an interpreter so they could participate in parent-teacher evenings and other activities involving their children.

The Rothschilds have retained sign-language interpreters at their own expense, paying an estimated $2,000 through the 1988-89 school year, according to the decision.

The couple maintained that they are denied equal opportunity to participate in school programs and to consult with school district personnel concerning their children.

They sought relief under the federal Rehabilitation Act of 1973, which says any organization receiving federal aid cannot discriminate against the handicapped.

The school district claimed that the parents do not qualify under the act because they are not students.

Goettel said that the regulations of the act define reasonable access for a deaf person as including a sign-language interpreter.

''Without the provision of a sign-language interpreter, the plaintiffs are de facto barred from the participation in the school district's programs for parents,'' Goettel wrote. ''This is not a case where the relief sought by the plaintiffs would be cumulative or duplicative of services they are already receiving.''

Goettel added, however, that the district's obligation ''is limited to school-initiated conferences incident to the academic and-or disciplinary aspects of their child's education. To the extent that the plaintiffs wish to voluntarily participate in any of the plethora of extracurricular activities that their children may be involved in, we think they, like other parents, must do so at their own expense.''

Attorneys for the school district did not immediately return phone calls.

In Camden, N.J., a deaf Rutgers University law student won a court order Monday forcing the school to provide her with classroom notes.

U.S. District Judge Stanley S. Brotman ordered the university's law school not to hold two classes attended by Karen Prince unless she receives notes within 24 hours of each class.

Ms. Prince sued under the same law as the Rothschilds.