Since Friday, the girls have turned off their cell phones and their computers. Now that it's after dark on Saturday night, they will play until sunrise.
Walking on the Sabbath to the homes of friends, they have talked to each other all day.
Now they will talk all night.
At the Jewish Community Center of Greater Baltimore on Park Heights Avenue, 18 teenage girls are celebrating Motzai Shabbos - the night after Sabbath - with activities like movies, swimming and exercise.
The group of mostly Orthodox girls will feast on their own versions of the staples of teenagehood - kosher pizza and ice cream. They will play basketball in long skirts and socks. They will work out for hours, on and off, while watching too many episodes of Full House.
The overnight is part of a trend at community centers, which increasingly are playing host to a more public brand of slumber party that sometimes includes entire families. Some YMCAs and the National Aquarium in Baltimore have offered them.
On this night at the JCC, 18 girls - most of them 13 or 14 - will travel the familiar arc of so many girls' slumber parties, from hyperactivity to glassy-eyed endurance, from conversational intimacy to dismissive cool. But they'll do it under the watchful eye of a 22-year-old chaperone who is Orthodox herself. They'll have a basketball court, workout rooms and empty halls to roam instead of only a darkened basement or living room to contain their giggles and guffaws.
Jewish Outreach Information Network for Teens (known as J.O.I.N.), which operates the program, is smart enough to advertise this event as a "girls' all-nighter." It is a "sleepover" only in this way:
Sleep is so ... over.
9 p.m.: The night is young, and already Shira Ocken, the girls' supervisor and J.O.I.N. teen coordinator, must set limits. She switches the teen lounge television to a basketball game. "I don't want this to be the place where they come and watch MTV," she says.
Because each family sets different rules for the girls, Ocken must strike a balance between enforcing some standards and letting 13-year-olds be 13-year-olds. Her goal: To create "a good safe environment for them to chill."
Hadassi Wiener, 14, and her 13-year-old friend Yaffa Luchansky - students, like many of the other girls, at Bais Yaakov Middle School - debate over whether to swim first, or hit the cardio room. (Swimming wins, after Hadassi - "Dassi" to her friends - determines that everyone is swimming now.)
9:45 p.m. Eight girls are in the pool. There's already been one fully-clothed dunking, and a mini-debate over who's hotter: Chad Michael Murray or Ashton Kutcher.
10:15. As music by the Jewish boy band Blue Fringe plays, 13-year-old Bunny Friedman begins her dominance of the ping pong and pool tables in between quick chats on her cell phone, which plays the William Tell Overture. "I don't play for fun," she warns. "I play to win."
Shana Tobesman, 14, checks her watch. "It's only 10:15," she sighs. "How sad is that?"
10:45 p.m. Time to hit the cardio room, where girls take to the treadmills and elliptical trainers while belting out parodies of a commercial for an album of Ultimate Love Songs. They work out in a frenzy for all of 15 minutes, then proceed to eat pizza.
11 p.m. Basketball - black skirts against other kinds of skirts (and a few pajama and sweat pants). Three girls walk in wearing peel-off facial masks. Says Dassi: "It clears your face and it's so cool." Says Amanda Schuster, 13: "That's so weird. It's freaking me out."
11:30 p.m. Everyone gathers for a workshop on body image. The visiting workshop leader asks the girls to turn off their cell phones, and to speak in turn. This is difficult.
Amanda is asked to form a basket with her arms. Her friends, old and new, are to share what knowing Amanda tells them about life. "I see a lot of beauty and cuteness," says one. "She's very comfortable with herself," says another.
On a pad of paper, Rachel Weissmann, 13, has been charged with writing it all down. "WE LOVE YA AMANDA," she freelances at the end.
They end with a meditation exercise, during which they lie on the floor and try to stifle giggles at directions such as "let your belly expand." With their eyes closed and faces slack, they look like babies again.
1:38 a.m. Invasion of the studio where the bouncy exercise balls are kept, begging to be draped upon. A couple of girls jump rope in bursts. In the lounge, another group cuddles up on chairs and couches to watch the movie Napoleon Dynamite.
2 a.m. Back to the fitness room. The lighting has taken on a wee-hours, too-bright quality. More workouts. Cartwheels across the floor. Air guitar.
2:45 a.m. The movie Dodgeball is on. Ocken wields the remote control. She's previewed the movie, which some of the girls asked to see. She fast-forwards through one suggestive scene, then another.
A bit later, still playing pool, Bunny will wonder why. "Everybody's already seen the movie," she says.
4 a.m. Some girls are wandering the halls, trailing their sleeping bags and pillows like young nomads. Some sprawl out in the movie room. Surely, now they will sleep.
"I'm going to bed," announces Menucha Frischling, 14. "I've never stayed up this late before. I'm a party pooper."
Says Bunny: "Who wants to play basketball in the gym?"
4:30 a.m. Somebody has put on Raising Helen. Menucha cries as a brother and two sisters are orphaned and forced to live with Kate Hudson. From the other room: The thwop, thwop, thwop of ping pong.
5:00 a.m. A frantic search for spoons. "I heard there was chocolate-chip cookie dough," says Menucha. She scoops the ice cream into a plastic cup, adds rainbow sprinkles, and finishes with a generous dollop of chocolate sauce.
"Guys," says Rachel, "I think we are going to have to work out again."
5:30 a.m. Ahead lie orange juice and doughnuts, parents pulling up by 8 a.m., a Sunday when studying for Monday's big test may lose out to the impulse to nap.
But now, as dawn approaches, the girls are reveling in their triumph over the clock. And already planning the next time.
When one girl mentions that she brought an air mattress, Rachel reacts with disbelief that it hasn't been inflated.
Not because she wants to rest.
"Omigod!" she says. "We could have gone mattress-sliding!"
If you want to sleep over
The Jewish Community Center of Greater Baltimore holds Motzai Shabbos (after Sabbath) nights for middle-schoolers and high schoolers at its Park Heights campus, 5700 Park Heights Ave.
The programs - usually until midnight and occasionally overnight - take place about one Saturday night a month for each gender. Motzai Shabbos is sponsored by the Jewish Outreach Intervention Network. Fees for overnights are $15 for members, $20 for non-members; regular Motzai Shabbos programs are free. Information: 410-542-4900 x229 or www.jcc.org, or by e-mailing firstname.lastname@example.org.