THE AMERICAN Film Institute has a rich selection of series (including the Yugoslavian film festival) going on. This weekend: "Preview/Review" premieres The Cure in Orange (Friday, 6:30; Sunday, 3; Monday, 8:30) -- a 1987 British documentary about the band The Cure, and Maurice (Sunday, 8:45) the James Ivory-Ismail Merchant adaptation of E.M. Forster's novel. (It opens here commercially next month.) It's $4.50 for nonmembers. Call 785-4600.

The Washington Project for the Arts has assembled a remarkable series of shorts, documentaries and features on Vietnam. It includes Sam Fuller's 1957 China Gate -- one of Hollywood's first films to show American presence in Indochina (September 29), Emile de Antonio's 1969 In the Year of the Pig and Joseph Strick's Oscar-winning Interviews with My Lai Veterans (both October 27). "Images of Vietnam: The Struggle for Memory" (which runs through December 15) will be shown Tuesday evenings at the American Film Institute and periodically at the Martin Luther King Memorial library auditorium and the Museum of Natural History's Baird auditorium.

This Tuesday at the AFI (at 8:45), it's Mills of the Gods: Vietnam, a 1965 documentary made by Beverly Fox for the Canadian Broadcasting Corporation, featuring interviews with soldiers in the field. It's screened with the 1962 CBS doc End of an Empire, plus Why Vietnam (a 1965 Department of Defense film shown to servicemen before they left for war), and The People's War, an equivalent propaganda film made by the North Vietnamese. Admission is $5 for nonmembers. The other films are too numerous to mention but include the 1966 Academy (foreign doc) winner The Anderson Platoon, made by Pierre Schoendorffer (October 6); Joris Ivens' 1968 Seventeenth Parallel -- a film sympathetic to the North Vietnamese (October 13); and the CBS compilation documentary Vietnam: An Historical Document (October 20), produced by CBS News after the fall of Saigon. WPA is also planning appearances by some of the filmmakers (including de Antonio, Strick, Wallace Terry and others); as well as an October 30 panel discussion, "The Media War: The Role of Media and Film in the Public Perception of Vietnam." Call the WPA at 347-4813.

The Smithsonian Resident Associates features a Tuesday-evening, five-film series made by the first group of post-Cultural Revolution graduates from the Beijing Academy. Beijing screenwriter Huang Zong-jiang will introduce the series and talk about current Chinese cinema. The films are Black Cannon Incident (Huang Jianxin, 1985, shown Tuesday); In the Wild Mountains (Yan Xueshu, 1986, September 30); A Girl From Hunan (Xie Fei and Wu Lan, 1986, October 7); Sacrificed Youth (Zhang Nuanxin, 1985, October 14); and Yellow Earth (Chen Kaige, 1984, October 21). Series tickets, $27 nonmembers, $22 members. Call 357-3030. The films roll at 8.