The Metropolitan Washington Planning and Housing Association, a non-profit organization, will discuss historic preservation in Old Anacostia at its annual meeting today from 10 a.m. to 1 p.m. at the Anacostla United Methodist Church at 14th and U streets SE. A walking tour of the neighborhood and a session of the group's Home Repair Workshop are planned.

Courses in architecture and construction, the "anatomy of a house," property law, real estate business records and real estate mathematics are scheduled during February by the Arlington Distributive Education Service and the Northern Virginia Board of Realtors. For information, call 558-2581.

The Alexandria Adult Distributive Education Department and the Northern Virginia Board of Realtors will offer a course in real estate residential financing at T.C. Williams High School starting Wednesday. For information, call 836-2812.

A sectional map amendment for the northwestern part of Prince George's County is available for public inspection and will be the topic of hearing Feb. 23 at Laurel Senior High School, the county Planning Board announced. It is on display at the Maryland-National Capital Planning Commission offices in Riverdale, in the office of the clerk to the County Council in the County Courthouse in Upper Marlboro, the Laurel Planning Commission, the Stanley Memorial Library and the Beltsville Library.

The Department of Housing and Urban Development and the Maryland Association of Realtors announced that they have signed a "voluntary affirmative fair housing marketing agreement" that sets out specific policies to guarantee the rights of all persons when renting or purchasing programs to inform "the monority community" of homes listed for sale or rent by realtors, the Maryland association said.