30 THINGS TO DO IN April

1 PROCEED with caution. Today is April Fools' Day.

2 SHOWER a four-legged friend with love. The A.S.P.C.A. recognizes April as Prevention of Animal Cruelty Month.

3 SPRING forward and let the sun shine in. The days last a little longer now that daylight saving has begun.

4 MAKE your head look bigger than your body. Learn Karl's secret. The Karl Lagerfeld Diet is in bookstores now.

5 GET lost in the voice. Billie Holiday: The Ultimate Collection CD/DVD is released in honor of Lady Day, who would have turned 90 this month.

6 DRESS the part. The Martha Graham Dance Company's opening gala commences its spring season.

7 KEEP your eyes on the sky this week as international kitefliers flock to Berck-sur-Mer, in France, for Europe's largest annual kite festival.

8 GUESS who's coming to dinner. Sidney Poitier will receive the 2005 Rick Weiss Humanitarian Award in Palm Springs tomorrow.

9 SERVE and volley your way into tennis star Maria Sharapova's 18th-birthday bash, in New York City, sponsored by Motorola. S Maroon 5 will perform.

10 SWOON over Billy Crudup up close. He stars in Martin McDonagh's The Pillowman, at the Booth Theatre, in N.Y.C.

11 EXPERIENCE the extraordinary life of a legendary jazz bassist. Keeping Time: The Life, Music, and Photographs of Milt Hinton airs tomorrow night on PBS.

12 ADOREI'opera with France's First Ladies Mme. Bernadette Chirac and Mme. Claude Pompidou at the Opera National de Paris performance of Wagner's Tristan et Isolde.

13 CHEERS. Artist Eric Fischl has designed the label for Bedell Cellars' 2001 Vintage Merlot Reserve, a limited edition selling for $200 per magnum through the month.

14 LIVE well. "From Jet Set to Jeans: The Wardrobe of Doris Duke," an exhibition of the billionairess's designer threads, is on display at Rough Point, her home in Newport, R.l.

15 BELIEVE Benjamin Franklin: "Nothing is certain but death and taxes." File your returns by today.

16 KEEP the faith and recognize the noble aspirations and cultural achievement at the recently opened Museum of Catholic Art and History, located in New York's East Harlem.

17 EXPAND your artistic horizons. The new Walker Art Center, in Minneapolis, now a 17-acre campus with gallery space, a screening room, and a theater, opens today.

18 LAUGH at Dazed & Abused,Kinvara Balfour's hilarious play about modern social behavior, onstage at London's Etcetera Theatre through the end of the month. Don't miss it.

19 LINE UP for tickets. New York's 4th Annual Tribeca Film Festival kicks off tonight.

20 DONATE to one Sweet Charity.Christina Applegate stars in Neil Simon's musical-comedy favorite, opening tomorrow on Broadway, at the Al Hirschfeld Theatre.

21 TRAVEL to the land of rum, cigars, and forbidden dancing. The New York Public Library's Young Lions host their annual charity ball. "An Affair in Havana" is this year's Cuban theme.

22 GET reel. The fifth annual Arlene's Grocery Picture Show kicks off in downtown N.Y.C. This no-rules, funkified fest shows nearly every film submitted. Plus, free popcorn.

24 IGNITE your lightsaberl Don't miss the final day of one of the largest Skywalker-diehard gatherings, Star Wars Celebration III, at the Indiana Convention Center, in Indianapolis.

23 GATHER round the Seder table. Passover begins at sundown.

26 ERASE it. The N.Y.C. chapter of the National M.S. Society hosts its Dinner of Champions tomorrow at the Marriott Marquis, in Times Square. Marvin Hamlisch performs.

25 TOAST the environment. The 15th Annual Windows on Long Island Wine celebrates 34 local vineyards at Capitate, in New York City. Proceeds go to the Earth Pledge foundation.

27 TRACE Robert Mallet-Stevens's fashionable footprints through France. The Pompidou Centre opens a retrospective of the architect-designer's work today.

28 KEEP a clear head. There'll be more than 1,000 wines to taste when the 29th annual Monterey Wine Festival opens tonight.

29 DANCE the night away. Coldplay and Nine Inch Nails headline the Coachella Valley music festival, in Indio, Calif., this weekend.

30 PEN a paean to opera. Renee Fleming and Sir Elton John top the Houston Grand Opera's guest list tonight for the Golden Jubilee Gala.