Preparing to bare skin at the beach isn't the only kind of spring training going on right now in Manhattan.

When summer comes, and whole social circles have decamped to the East End, the social calendar makes a radical shift, to the weekend.

That means waking up on a Saturday and dressing for a brunch at 11, a boutique opening at 3, and a cocktail party at 7. Did someone want to go to the beach? There's always Wednesday.

Turning the weekday party muscles into weekend ones can be hard work, so, even though the East End social season doesn't start for a few weeks, New Yorkers got a jump start this weekend.

They gave up their sacred in-city weekend routines, such as sleeping late, dusting off the espresso machine, and eating dinner at home, in exchange for social commitments.

At 11 a.m. on Saturday, members of the New York Public Library patrons group for young families, the Cubs, headed to the Humanities and Social Sciences Library for a family concert by They Might Be Giants featuring songs such as "The Alphabet of Nations" and "Fibber Island." The event ended with peanut butter and jelly and Nutella and marshmallow fluff sandwiches (both of which, incidentally, would travel well to the beach). The event was perfect training for the Ovarian Cancer Research Fund designer shopping and family carnival benefit scheduled for July 26 in Water Mill, N.Y.

By 2 o'clock, at the meatpacking district boutique of fashion designer Adam Lippes, waiters were serving white wine and ice water on silver trays at a book signing and party for "Out," a collection of party snaps by Bob Colacello, now in its second printing. The event was good training for the parties for "Out" that will take place all over the East End this summer. At this one, guests included Susan Hess, Jacqueline Davis, and Samantha Perelman.

Mr. Colacello has a few important dates in Manhattan before he can decamp full time to Sag Harbor: the high school graduation of Miss Perelman on June 11 (at which she said she'll be wearing a white dress her father, Ronald Perelman, bought her), and the opening of an exhibit of photographs from "Out" (taken during his time at Andy Warhol's Interview magazine), on June 12, at Steve Kasher Gallery.

By nightfall, New Yorkers were not only training for the Saturday night summer benefits, they were raising funds for an East End cultural jewel: the Perlman Music Program, an intensive summer study program for musicians between the ages of 11 and 18, located in Shelter Island, N.Y.

Toby Perlman founded the program and convinced her husband, Itzhak Perlman, to get involved. He spends most days of the summer teaching there, joined by an esteemed faculty that includes a Juilliard viola professor, Heidi Castleman.

The event's honoree, Billy Joel, who has a boat-building business on Shelter Island, told of visiting the program and marveling at the students' talent.

"I wish I'd been able to go to a program like that," Mr. Joel said before a seated dinner at Daniel. "I studied classical piano for 12 years, but I didn't practice enough. I was supposed to be learning Mozart, but instead I'd write my own stuff."

He recalled his first meeting with Mr. Perlman, at a party in the Hamptons. "Someone offered to introduce me, and I thought, 'I'm gonna meet the Revlon guy,'" referring to Ronald Perelman (both men pronounce their last names the same way, and both men have homes on the East End).

"Now I know both of them, and they're both wonderful guys, but I have to say I think Mr. Perlman is vastly wealthier," Mr. Joel said.

"No," Mr. Perlman said. But Mr. Perelman is a donor to the Perlman Music Program, as are Steven Spielberg, Lisa de Kooning, Sidney and Morgan Stark, and Jay and Shoshana Dweck.

The Perlman Music Program has a fund-raiser in Shelter Island on July 25. The public is invited to student performances on June 21 and June 28, and on Fridays and Saturdays in July and the first weekend of August.

agordon@nysun.com