ART

Thereare many stories in the Depression-era photographs of Aaron Siskind, 60 of whose images are now on view at the National Museum of American Art. The prints were culled from several projects the photographer initiated before, during and after his involvement with the Photo League of New York, which he joined in 1936. Considered as a group, these pictures form an almost 20-year-long portrait of a section of what is perhaps America's most significant black neighborhood: the square block between 142nd and 143rd streets and between Lenox and Seventh avenues. There is a misery in many of the images, but there is a tenacious vivacity too. There are poverty and filth, and there is nobility.

Down the road from NMAA at the Washington Project for the Arts is another exhibit centered on New York's less privileged. This multimedia installation by Krzysztof Wodiczko and a host of collaborators features photographs taken during the past two or three years, mostly of homeless people, mostly in and around Tompkins Square Park in the East Village. But these photographs, projected images, video and "Homeless Vehicle," a utilitarian device designed by Wodiczko and David Lurie, do not constitute a documentary in the sense that Siskind's pictures do. This show, "New York City Tableaux: Tompkins Square/The Homeless Vehicle Project," is not the work of a chronicler, but of an activist. Where Siskind recorded with compassion -- with distance -- the lives of everyday people, Wodiczko's approach is one of advocacy. Siskind's show is on view through March 17, Wodiczko's through Jan. 20.

CLASSICAL

The Washington Opera's first new production of the 1990-91 season will also be the first major event of the 1991 Mozart bicentennial observance: "The Magic Flute," designed by Zack Brown and opening Saturday night in the Kennedy Center's Eisenhower Theater. At last report, the entire run was not only sold out, there was also a waiting list of more than 800 for returned tickets.

The final musical events of the pre-Christmas season will include a Choral Arts Society concert this afternoon and a the "Messiah" Sing-Along tonight in the Kennedy Center Concert Hall; the Maryland Camerata tonight at the National Gallery; and the Monumental Brass Quintet tonight in the Grand Foyer of the Kennedy Center.

The New York String Orchestra, a student ensemble recruited for the Christmas holidays each year, will perform Wednesday night in the Kennedy Center Concert Hall.

DANCE

It's that time of year again, when -- as predictably as the recurrence of the hibernal solstice -- the dance calendar is entirely filled by "The Nutcracker," in its various choreographic and dramaturgic manifestations but always with Tchaikovsky's enduringly enchanting music. The major professional productions hereabouts this week are those of the Washington Ballet, continuing its run at Lisner Auditorium through Saturday evening; and the visiting Donetsk Ballet from the Ukraine, which has extended its run at Baltimore's Lyric Opera House through next Sunday afternoon. Also worthy of note are a trio of school-based productions by the Maryland Youth Ballet (at Montgomery College Performing Arts Center), the Virginia Ballet (at W.T. Woodson High School in Fairfax) and the Metropolitan Ballet Theatre (at Montgomery College ).

POP MUSIC

December with Ahmad Jamal at Blues Alley has become a Washington tradition: The sterling pianist is there from Wednesday through New Year's Eve.

The original brother from another planet: Sun Ra and his Solar Arkestra bring their year-round holiday cheer to the 9:30 on Wednesday.

Booker T and the MGs are synonymous with Southern R&B, but usually you have to settle for the classic records: Thursday they'll be live at the 9:30.

Shirley Horn, who looks to be the hot jazz singer of 1991, begins to stoke the fires Thursday through Saturday at the One Step Down.

So long, it's been good to know them: After too many years of not enough, the Slickee Boys call it quits, but in grand style, with lots of alumni and friends, Friday and Saturday at the 9:30.