Pete Seeger and Leon Gieco perform Friday night at 8:30 at Montgomery Blair High School in Silver Spring (301-270-9090), not as listed in Sunday's Show section. (Published 10/23/90)

ART

For genteel Childe Hassam, the American impressionist, the Rockies were too far away, and too grandiose. The Hudson River Valley had been painted too often, and besides, it had no ocean. But Appledore seduced him. Appledore had everything -- solitude when wished for, flowers and rough rocks, and maid service and musicales, and, everywhere one looked, the twinkle of the sea.

Appledore, in the Isles of Shoals, is an outcropping of granite 10 miles off New Hampshire's coast. Hassam loved it loyally. "Childe Hassam: An Island Garden Revisited," the touring exhibition at the National Museum of American Art, is a record of his love affair -- with sunny summer holidays, tidal pools and poppies -- with the Appledore that lured him back nearly every summer for more than 30 years.

The show will remain at the NMAA through Jan. 6.

CLASSICAL

Most unusual events of the week: the Schubert, Schubert and Schubert festival, featuring the Auryn Quartet, soprano Brigitte Poschner-Klebel, clarinetist Siegfried Schenner, baritone Gordon Getty, double bassist Robert Dodelin and cellist David Soyer, Friday, Saturday and Sunday nights at Georgetown University's Gaston Hall; the Philip Glass Ensemble, with Glass, performing the music of the film, "Koyaanisqatsi," Thursday and Friday nights in George Washington University's Lisner Auditorium; Opera Americana performing Washington composer Garrison Hull's "Fashionable Vices," Saturday night in Gadsbys Tavern, Alexandria.

Two other Washington composers will be having world premieres of choral works this week: Daniel Gawthrop's "Four Seasonal Metaphors" performed by the Cathedral Choral Society today at the Washington National Cathedral and Thomas Beveridge's "All Things Bright and Beautiful," performed by the McLean Choral Society and Fairfax Symphony, Saturday night in Langley High School, McLean. It will be a busy week for choral music, with the Boys Choir of Harlem, Saturday night at George Mason University and Rossini's Stabat Mater performed by soloists and the Sanctuary Choir today at Mount Vernon Place United Methodist Church.

Soprano recitals this week will include Jessye Norman, Friday at the Kennedy Center and Martina Arroyo, tonight at the National Gallery.

One of the few orchestras that will not be playing in Washington this week is the National Symphony, ending its European tour. To fill the gap, you can choose among: the Leningrad Philharmonic, Thursday at the Kennedy Center; the Japan Philharmonic, Tuesday at the Kennedy Center; the Pittsburgh Symphony, Lorin Maazel conducting, today at George Mason University; the Handel Festival Orchestra, Friday and Saturday in the Terrace Theater; the Friday Morning Music Club Orchestra, today in the Terrace Theater; the Landon School Orchestra, tomorrow at the German Embassy; the George Mason University Symphony Orchestra, Tuesday in the Harris Theater; the D.C. Youth Orchestra, Saturday at Coolidge High School.

The Beaux Arts Trio, playing under the auspices of the Library of Congress Thursday and Friday at the National Academy of Sciences, will highlight the week's chamber music. Also worth noting: Charles Stier, clarinet, today at the Phillips Collection; the American Camerata, tonight at the University of the District of Columbia; Ciosoni, new music chamber ensemble from Tennessee, Tuesday night at Mount Vernon College.

Pianists of the week: Andre Laplante, Thursday night at the Canadian Embassy; Maria Grazia Sorrentino and Peter Hitz, Tuesday night at Meridian House.

DANCE

The Washington Ballet concludes a week of performances at the Kennedy Center Opera House with a final program this afternoon featuring ballets by Balanchine, Cranko and Fernand Nault. The lavishly gifted American dancer-choreographer Mark Morris brings his Brussels-based Monnaie Dance Group/Mark Morris to the Eisenhower Theater this week in the Kennedy Center's "Dance America" series, featuring two complete, alternating programs Tuesday night through Sunday afternoon. Sally Nash and the Last Minute Wood Company presents new and recent work at Mount Vernon College's Hand Chapel Friday and Saturday nights, along with guest artists Cynthia Thompson and Kate Trammell. The North Carolina-based Chuck Davis African-American Dance Ensemble appears in concert at the Publick Playhouse Saturday night. Kotobuki Kai, directed by Yoko Harada King, performs with guest artist Sachiyo Ito at the Hallam Theatre of Prince George's Community College Saturday night. Washington's Adrain Bolton Dance Company presents works by Bolton, Peter Romero, James Thurston and the late Jason Taylor in its new program at Dance Place Saturday and Sunday evenings.

POP MUSIC

Andy Summers's career hasn't been as arresting as it was in his long stint with the Police, but he's still a master of guitar nuances. At the 9:30 club Tuesday.

Robert Cray, that rare young bluesman, tag-teams with the Memphis Horns Wednesday at Constitution Hall.

Barry Harris, Beaver Harris and Ron Carter, a trio to be reckoned with, appear Friday and Saturday at the One Step Down.

Pete Seeger and Leon Geico, Argentina's Bob Dylan, shares the stage and probably a few political views Friday at Lisner Auditorium.