At its annual fund-raising dinner last week, the Advertising Council honored two agencies for their work on pro bono campaigns. Launched earlier this year, McCann-Erickson’s campaign for obesity prevention features love handles and extra chins that their owners have lost (because they’ve used the stairs instead of the escalator or taken a walk on the beach). Like Archimedes, Robert Frost, a creative director of the campaign, had his eureka moment in the bath. “I was laying there and my gut was sticking out of the water, and I said, I wish I could lose this gut. That’s what people usually say – so we made a whole list of the different parts we could lose.”

The other campaign honored, by FCB-Souther California, features Smokey the Bear, the 60-year-old icon of wildfire prevention.

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Smokey the Bear was also an inspiration for New York City’s Urban Park Rangers program, which marked its 25th anniversary with a reunion yesterday at the Loeb Boathouse. A former commissioner of parks and recreation, Gordon Davis, started the program in 1979 to “tangibly and clearly show that we hadn’t given up on our parks.” Rangers offer educational programs and greet visitors. Mr. Davis began the program with a borrowed National Park Ranger uniform, the support of Mayor Koch, and a little creative accounting. “You didn’t know this at the time, but those of you in the class of ’79 were all lifeguards,” Mr. Davis said. Most rangers have stayed in public service – hundreds still work in the parks department or for other city agencies. “It’s no coincidence that the 25 years we’ve had the ranger program parallels the renaissance of the parks system,” said the current commissioner, Adrian Benepe, who was in the founding class of rangers.

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The Coalition for the Homeless’s Art walk fund-raiser relies on the generosity of artists. Tonight, hundreds of donated works will be auctioned at a black-tie dinner honoring artist Edward Ruscha and collector Donald Marron. About a dozen artists also opened up their studios to the public on Saturday afternoon, including Julian LaVerdiere, Louise Fishman, and Lyle Ashton Harris. Another party and auction on Saturday night drew model Natalia Vodianova and “Saturday Night Live” comedian Molly Shannon, as well as Sue de Beer (who has a show opening at the Whitney in March) and three former artists-in-residence at the Studio Museum in Harlem, Kira Lynn Harris, Kehinde Wiley, and Mickalene Thomas. Whitney curator Shamim Momin was a co-host.

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Bargain-hunters got a treat this weekend at the Goddard Riverside Community Center’s annual book fair. Cookbooks, art books, and hot-off-the-press fiction sold at 50% off retail – all donated by the publishing industry. The event raised about $450,000 for the center. “It’s grown so much,” said board member Florence Janovic. “It started as a neighborhood event, now people come from all over the city to shop,” said the center’s chairman, Mary Ellen Rudolph.

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Male and female dancers wearing elaborate headdresses tried to entertain the model-artist crowd at Indochine’s 20th anniversary party Friday night. But 9-year-olds Quest Suliman (son of the maitre d’) and Eliza Callahan (daughter of one of the owners) stole the show. When the rock band Spalding Rockwell played, the children rocked out on stage.