The works of Thomas Downing, one of the last Minimalists and one of the last of the hard-edge Washington Color School painters, are on display at the Phillips Collection and the Addison-Ripley Gallery, through Sept. 8. These strange, tart, idiosyncratic yet warm paintings are well worth seeing for their animation, their movement. Simon Gouverneur's intricate new paintings are also at the Phillips. CLASSICAL MUSIC

This evening wraps up the week-long appearance at Wolf Trap's Filene Center of the New York City Opera, with a repeat of its splendid "Madama Butterfly."

Starting Wednesday at Wolf Trap will be four successive nights of Bach and Handel, celebrating the 300th birthdays of each. The National Symphony is going first class on these. Eminent Baroque specialist Christopher Hogwood, who recently directed two memorable weeks with the orchestra at the Kennedy Center, will be in charge, and famed soprano Elly Ameling will sing on Saturday and Sunday. DANCE

The festival of 10 area modern dance choreographers and companies, Washington Dance Directions '85, repeats its three programs Thursday through Saturday at the Marvin Center Theater. At Montgomery College, Rockville, Cathy Paine & Friends, one of Washington's foremost troupes, performs Friday night in the exceptionally handsome, year-old Performing Arts Center. A notable New York troupe, Elisa Monte Dance Company, appears Friday night at the University of Maryland's Tawes Theatre. Performing Saturday and Sunday as part of Sisterfire, the festival of women artists in Takoma Park, will be two unusual groups -- Edwina Lee Tyler & Piece of the World, an all-women's African dance and percussion ensemble, and Urban Bush Women, a much-hailed ensemble combining contemporary techniques with Afro-Caribbean folklore and ritual. FILM

"The Dream Is Alive," filmed on the space shuttle in the new, extraordinarily vivid IMAX format, will open to the public Saturday night at 7:45 and 9 p.m. at the Langley Theater of the Air and Space Museum.

The free summer cinema series at the National Theatre's Helen Hayes Gallery continues with Ernst Lubitsch's comedy classic, "To Be or Not to Be," starring Carole Lombard and Jack Benny, who, indeed, performs Hamlet's soliloquy.

The Five European Directors series continues at the American Film Institute, with films of Andrzej Wajda, Werner Herzog, Franc,ois Truffaut.

The American Screenwriters series continues at the Library of Congress' Mary Pickford Theater with Preston Sturges' "Easy Living" (written by Mitchell Leisen), Tuesday at 7:30, and Joseph Mankiewicz's "There Was a Crooked Man" (written by David Newman and Robert Benton), Thursday at 7:30.

Tomorrow and Tuesday, the Sidwell Friends School will show Philip Borsos' lovely "The Grey Fox," at 7:30 and 9:15, followed Wednesday and Thursday by Paul Bartel's black comedy "Eating Raoul."

Among current releases, John Huston's "Prizzi's Honor," a dark and funny film about the American Dream, with an indelible performance by Jack Nicholson. POP MUSIC

Leon Russell brings Hank Wilson, the Mad Dog and others to the Bayou tonight.

Randy Newman may be bottom-billed to Billy Crystal at Wolf Trap tomorrow, but his beautifully wrought, state-of-the-heart narratives will outlast Crystal's sketches.

Two old guitar heroes hit the comeback circuit: Rory Gallagher, the blues-bashing Irishman, is at Club Saba on Tuesday and Wednesday, and Leslie West brings his reconstituted Mountain to the Bayou on Wednesday.

Phil Collins, the hottest male rocker on the scene right now, brings his Hot Tub Club to the Merriweather Post Pavilion on Friday, without Genesis but with Earth Wind and Fire's Phoenix Horns.

Friday is Reggae Night, with the determined Judy Mowatt at Kilimanjaro's Heritage Hall and the promising double bill of Third World and Jah Mallah at the Warner Theatre.

Saturday and Sunday bring the bigger and better Sisterfire to the fields of Takoma Park Junior High School. Among the outstanding acts: Sweet Honey in the Rock, Ronnie Gilbert and Ferron. The festival runs from 11 a.m. to 7 p.m. each day. THEATER

Sooner or later, it was bound to happen: "A Chorus Line," Broadway's longest-running musical, would turn up in a dinner theater. What's surprising is the confident, often exciting production, put together by the Harlequin Dinner Theatre in Rockville. The show plays all summer.

This is the last week to catch Peter Sellars' huge, controversial staging of the 19th-century melodrama "The Count of Monte Cristo" at the Kennedy Center's Eisenhower Theater.