Residents of Evergreen House, an Annandale retirement home, returned to the classroom recently at the invitation of students, faculty and staff of Holmes Intermediate School in Fairfax County. Sponsored by the Student Council Association as a community service project, the visit was designed to familiarize the senior citizens with current school programs and thank them for supporting education in the county.

After attending a musical assembly performed by the Jefferson High School Band, the guests visited several classrooms where they could compare contemporary instruction with their own schooling as youths. After a luncheon in the home economics department, the guests were entertained with a mime show performed by Holmes drama students. Later, each guest received a gift made by students in the mildly mentally retarded program.

Principal Ray Watson said Holmes' students "were enriched through their discussions with our guests and by the opportunity to serve others."

Five Bishop Ireton High School students recently were named the best delegation to the 1982 Hague Model United Nations, sponsored by the American School at The Hague, the Netherlands. About 2,000 high school delegates from around the world competed in debates at the session.

The Bishop Ireton delegation, made up of senior Mark Boespflug and juniors William Sullivan, Patrick Sims, Patrick Vaccarino and James Vick, was the smallest at the event. Most delegations had at least 15 members. Bishop Ireton's five-member group, led by debate coach Mark Williams, was instructed to represent South Africa and defend that country's foreign policy on problems ranging from economic affairs to human rights.

Eleven high school seniors from Northern Virginia are among 300 selected nationwide for the honors group of the 41st Annual Westinghouse Science Talent Search, a national competition to encourage young scientists. The program has been sponsored since 1942 by the Westinghouse Educational Foundation and the Westinghouse Electric Corp. and conducted by Science Service, a nonprofit organization.

The winners were selected on the basis of their independent scientific research projects. Their Talent Search sponsors will recommend them for admission and financial assistance at colleges and universities.

Named to the honors group were: James Mackey IV, 17, of Vienna, a student at Gonzaga College High School in the District; Henry Edgar Cardwell, 17, Christine Ann Mota, 17, and Joseph Carroll Sullivan, 18, all of Alexandria and T.C. Williams High School; John Joseph McGovern, 17, and Byung Wook Ye, 17, both of Arlington and Yorktown High School; Carol Margaret Hawk, 17, of Falls Church and George Mason Senior High School; William Milton Hawkins, 17, and Patricia Eileen Nakache, 16, both of McLean, and Shawn Gregory White, 17, of Falls Church, all of McLean High School; and Karen Suzanne Brown, 17, of Springfield and West Springfield High School.

Justin W. Collat of Falls Church has been appointed director of the American Chemical Society's membership division. A former faculty member at Ohio State University, he joined the American Chemical Society staff in 1966. He has held several administrative positions at ACS, most recently as head of the grants and awards program. In his new position, Collat will oversee the Society's worldwide membership of 123,000 chemists and chemical engineers.