St. Patrick's Day * Gaithersburg holds its third annual St. Patrick's Day Parade Saturday at 10 at Washingtonian Center, I-370 and Washingtonian Boulevard. Admission is free. Call 301-258-6350.

* The annual St. Patrick's Day Parade in Washington begins Sunday at noon at Seventh Street and Constitution Avenue NW (Metro: Judiciary Square, Archives/Navy Memorial), and marches west to 17th Street NW (Metro: Federal Triangle) with more than 100 units, including bands, floats, dancers and classic cars. Standing room is free. Grandstand seats near the Washington Monument are $5; for seats, call 301-384-6533. For information, call 202-637-2474.

A Wild Centennial

The National Wildlife Refuge System marks its 100th birthday Saturday from 10 to 3 with live animal presentations, nature songs and stories by Billy B., tram tours, children's crafts and other activities at the National Wildlife Visitor Center, 10901 Scarlet Tanager Loop, off Powder Mill Road between Route 197 and the Baltimore-Washington Parkway in Laurel. Admission is free. Call 301-497-5763.

Purim Festival at Book Fair

A Bob Brown Puppets show, arts and crafts activities, food and games are featured at the Purim Festival Sunday from 1 to 3:30 at the Jewish Community Center of Greater Washington, 6125 Montrose Rd., Rockville. The festival, which commemorates the ancient Persian Jewish community's victory over oppression, is part of the center's 15th annual Children's Book Fair, which is open Sunday from 11 to 5, Monday and Tuesday from 9:15 to 5, Wednesday from 9:15 to 8 and Thursday from 9:15 to noon. Admission to both events is free; there are fees for some festival activities. Call 301-230-3756 for information about the festival, and 301-881-0100, Ext. 6797 about the book fair.

NSO for Everybody

* The National Symphony Orchestra and principal pops conductor Marvin Hamlisch showcase the "Stars of Tomorrow" Friday and Saturday at 8 in the Kennedy Center Concert Hall (Metro: Foggy Bottom/GWU, with free shuttles). Tickets cost $20 to $72.

* Thomas Wilkins conducts the NSO in "Music From the Movies" family concerts, featuring scores from "Star Wars," "E.T.," "Harry Potter" and other films, Sunday at 1 and 3 in the Kennedy Center Concert Hall. Most tickets cost $13.

Call 202-467-4600 (TDD: 202-416-8524).

'Henry' Goes to War The Washington Shakespeare Company opens its production of "Henry V" with "pay-what-you-can" previews Friday, Saturday and Monday at 8 at the Clark Street Playhouse, 601 S. Clark St. (Metro: Crystal City). Eleven actors will play more than 30 roles in Shakespeare's tale of the vastly outnumbered English soldiers who crushed the French at Agincourt early in the 15th century. Tickets go on sale at the box office one hour before each show. The run continues through April 26; regular prices are $22 to $30. To order, call 800-494-8497; for information, call 703-418-4808.

Environmental Film Fest

The 11th annual Environmental Film Festival, featuring 130 documentary, animated, feature, archival and children's films, runs through March 23 at museums, embassies and other locations in Washington. This weekend's schedule includes these free showings:

* "The Octopus Show" and the animated "Cartoon Sea," Friday at noon in Baird Auditorium at the National Museum of Natural History, 10th Street and Constitution Avenue NW (Metro: Federal Triangle).

* Award-winning nature documentaries from England's 2002 Wildscreen Film Festival, Saturday from 11 to 5:30 and Sunday from 11 to 5 in Baird Auditorium.

* "Ansel Adams," a portrait of the famed American photographer, Saturday at 2 in Carmichael Auditorium at the National Museum of American History, 14th Street and Constitution Avenue NW (Metro: Smithsonian, Federal Triangle).

Most screenings are free. Call 202-342-2564, or visit www.dcenvironmentalfilmfest.org.

Tango and Beyond

Argentina's Santa Fe Guitar Quartet presents a wide-ranging evening of contemporary and classical music by J.S. Bach, Astor Piazzolla, Pat Metheny, Bela Bartok and other composers Friday and Saturday at 8 as part of the Dumbarton Concert Series at Dumbarton Church, 3133 Dumbarton St. NW. Tickets cost $26, $22 for seniors and students. Call 202-965-2000.

Kirov Plays Mahler Valery Gergiev conducts the Kirov Orchestra of St. Petersburg in Mahler's Symphony No. 9 and other works Tuesday at 8 in the Kennedy Center Concert Hall (Metro: Foggy Bottom/GWU, with free shuttles). Olga Kern, first female winner of the Van Cliburn gold medal since 1969, is the piano soloist. Tickets cost $30 to $95. Call 202-467-4600 (TDD: 202-416-8524).

-- Compiled by Larry Fox

Washington's St. Patrick's Day Parade on Sunday will feature marching bands, floats and dancers.capttwocaptthree