The Opera Society of Washington is repeating last fall's highly successful cooking demonstration fund raiser again this spring.

Five classes, four in embassy kitchens and one in the kitchen of the Secretary General of the Organization of American States, will begin Monday, April 18.

Each chef will prepare one or two national dishes beginning at 10:30 a.m. Lunch at the embassy follows with the exception of OAS Secretary General, Alejandro Orfila: The demonstration and lunch will be at his residence. It is the first of the series to be followed on Tuesday, April 26 at the German Embassy; Wednesday, May 4 at the Swedish Embassy; Thursday, May 12 at the Iranian Embassy and Friday, May 20 at the Ivory COast Embassy.

The cost for the series, which is limited to 16 people, is $350, $300 of which is tax deductible. To reserve a space call Dru Taylor at 333-5011 or Sally Davidson at 333-7691.

A new Ward Three Food Stamp Certification Office opened earlier this year in the Regency House, 5201 Conn. Ave. NW. The office, open Tuesday from 9 a.m. to 4 p.m., services many elderly people who live in the neighborhood.

The office needs volunteers who will be trained. Call 234-5678 for more information.