Sure, New York empties out this time of year. But there’s more to summer in the city than hanging out at a faux beach in Queens. The last gasp of August can be enjoyed at the many free museum parties that mix art with music, drinks, and socializing — all in their own fashion. With so many parties on offer, flitting from one bash to the next is only a matter of scheduling.

With two soirees happening at opposite ends of town, Friday nights are a social-calendar dilemma. On the Upper East Side, the Cooper-Hewitt, National Design Museum (2 E. 91st St. at Fifth Avenue, 212-849-8400) presents Design + DJs + Dancing, which is best described as club + bar + garden party. Food (up to $6), beer and wine ($6), and other mixed drinks ($9) are plentiful, and pulsating beats echo throughout the cavernous halls. With a changing lineup of DJs, such as Scott Hardkiss, Steve Travolta, and DJ Sabo, “many of the attendees may first come because they’re fans of a particular DJ,” the museum’s press manager, Laurie Olivieri, said. “But then [they] walk through the museum’s exhibitions and discover they’re fans of design as well.”

On a recent evening, even though a thunderstorm just blew into town, a crowd of 75 or so people wandered around the breathtaking gardens. There were well-dressed businessmen, sophisticated foreigners, and the occasional stroller-pushing mom. Despite the formal attire, a casual atmosphere reigned, creating a lively party (through September 8, Fridays, 6–9 p.m.).

Chelsea’s K2 Lounge at the Rubin Museum of Art (150 W. 17th St., between Sixth and Seventh avenues, 212-620-5000) provides the most downtownlike atmosphere and the latest closing time (midnight, or later if patrons wish to stay). Though the galleries, which are replete with Himalayan art, are open until 10 p.m., most people seemed more taken with the friendly bartenders, concert series, and a film screening on the lower level.

The spacious galleries belie the intimate setting, both of which make the K2 Lounge the best place to bring a date.Those looking to find a date might want to head here, too. More upscale than the average watering hole, but more inviting than a trendy lounge, the atmosphere is such that complete strangers can wind up having serious conversations. “We’re excited that the K2 lounge is attracting a younger group,” the museum’s coordinator for external affairs, Karen Kadmey, said. Two-for-one drink specials (6–7 p.m.) can’t hurt, either (year-round, Fridays, 6 p.m.–midnight or later).

Saturday evening is lighter on gatherings, which allows for an impromptu visit to the Metropolitan Museum’s Iris and B. Gerald Cantor Roof Garden.The current installment by Cai Guo-Quiang features a glass panel, dead birds constructed from papier-mache, and resin crocodiles with items confiscated at airport checkpoints. Even with the art, the true feast for eyes is the view of the city skyline (through October 29, Fridays and Saturdays, 9:30 a.m.–9 p.m; Tuesdays–Thursdays and Sundays, 9:30 a.m.–5:30 p.m.).

On Sundays, an art-party tour can wind down pleasantly at the Museum of Modern Art (11 W. 53rd St., between Fifth and Sixth avenues, 212-708-9400). Its outdoor Summergarden concert series attracts people in droves with classical music by Juilliard students and jazz concerts. The concerts are free, and that means even those who arrive early can find themselves sitting on the marble floor instead of a chair. Patience proves to be a virtue, however; as the night progresses, seats inevitably open up. More than any other party, etiquette is required here: There’s no sitting on the garden stairs, no flash photography, and no loud conversation. Still, the milieu is friendly and warm. Occasionally, the music is accompanied by the whir of a helicopter or the sound of city traffic, but it’s a small price to pay for the opportunity to hear breakout pieces of music. Between numbers, concertgoers can head to the museum’s food cart, which serves ice cream ($3) from Il Laboratorio del Gelato (through August 13, Sundays at 8 p.m.).

But Manhattan doesn’t have the lock on such events: The museum-party circuit continues apace in the outer boroughs. On the first Saturday of each month, the Brooklyn Museum offers a vibrant selection of art, film, music, and more with the Target First Saturdays program (200 Eastern Parkway, 718-638-5000). While the free festivities roll on, the museum stays open until 11 p.m. and offers something rarely found in Manhattan: parking (from 5 p.m., $4). But be forewarned: The program runs year-round, except for the first weekend of September, when another local event takes over (year-round, first Saturday of the month, 5–11 p.m.).

Perhaps the best-known museum party is P.S.1’s Warm Up (22-25 Jackson Avenue at the intersection of 46th Avenue, 718-784-2084), a reliable place to see and be seen.Voted the “Best Club” in 2005 byTime Out New York, the lineup for the parties remaining this summer features an international roster of DJs. (through September 2, Saturdays, 3–9 p.m.)

For an early start to next weekend, the Jewish Museum’s SummerNights soiree (1109 Fifth Ave at 92nd Street, 212-423-3200) is worth planning ahead for. Every Thursday the museum provides a different line up of television programs from the National Jewish Archive of Broadcasting, which is part of its permanent collection. “We wanted to have an evening where we were offering a multifaceted experience,” the Jewish Museum’s communications director, Anne Scher, said.

And multifaceted, it is. One evening started off with episodes of “The Adventures of Superman,” “Superman: The Animated Series,” and “Smallville,” which were shown as a tribute to the superhero’s Jewish creators Jerome Siegel and Joseph Shuster. Later, the strains of Latin music provided by Marta Gomez lured the crowd to frolic and merriment. People milled about inside between programs, coming and going from the cash bar or stopping by the museum’s Café Weissman, where drinks are just $5.

It’s a crowd of all sorts: college students, senior citizens, and everyone in between. The setting here is like a lowkey gathering of jovial friends — at the home of a lucky pal who happens to own a theater-sized screen and cavernous auditorium (through September 7, Thursdays, 5–9 p.m.).

To judge one event as better than another is like comparing Monet to Warhol, but the Cooper Hewitt’s Design + DJs + Dancing is a winner. With ambient grooves, food and drinks, and a garden that is second to none, it’s a true urban pleasure.

If there is any drawback to all the art parties, it’s that focusing on the art can at times be difficult with so many distractions. Still, each taste of culture is like an appetizer that encourages the desire for more. Which is all to the good.