He works as a mechanical engineer from 10 a.m. to 6:30 p.m. She works at the National Board of Medical Examiners from 7 to 3, except on exam nights, when she gets home at 11. During one hectic - but not atypical - week, their daughters, 10-year-old Ella and 8-year-old Lily, had dentist appointments after school on Monday. On Tuesday, Lily's Brownie troop met. Wednesday was the Reading Olympics at Bala Cynwyd Elementary School. Thursday, both girls had guitar lessons.

The weekend is no respite; there are ski lessons in the winter, basketball in autumn, and soccer in fair weather. No wonder that, when Saturday night limps around, the last thing Penny and Joe Garcia want to do is hire a babysitter and head for the door.

"By the time the evening comes," Penny says, "we want to melt into the sofa and watch television, not get dressed up and go out."

The Garcias have good company - a growing cadre of parents who are exhausted, cash-strapped, worried, or guilt-ridden (or all of the above). They can be found in their jammies at 8 on a Saturday night, streaming Hotel for Dogs on the flat-screen and eating pizza with their kids.

Call it the No Babysitters Club.

No one keeps statistics on babysitters; they are unregulated, unlicensed, and, according to the U.S. Bureau of Labor Statistics, lumped together with those who run family day-care centers or work in child-care facilities. But testimony from parents, researchers, and popular parenting message-boards points toward a generational shift in how we think about and use - or don't use - babysitters.

"The thing I've heard about the most is people not going out at all - not because they can't find a sitter, but because they're so intimately involved with their children that they don't want to go out without them," says David Anderegg, a Bennington College professor of psychology and author of Worried All the Time: Rediscovering the Joy in Parenting in an Age of Anxiety.

That's only partly true for the Garcias, who acknowledge that their weekend social life "revolves around the kids." They hire a sitter perhaps four evenings a year - usually for a dinner out on their birthdays or anniversary, or the rare party to which children are not invited.

Cost is the other issue. Add the babysitter's charge - the going rate for teens is $7 to $12 per hour - to the tab for dinner, a movie, and parking, and an evening out can easily cost $150. That's why, for a treat, Joe will sometimes drive to Mikado in Cherry Hill for takeout. "We don't have to pay a babysitter, we don't have to pay a tip, and we get our sushi fix," Penny says.

It was different just a generation ago. When Penny, 49, was growing up in Norfolk, England, her parents went to a dinner-dance every Saturday night. "We had a lot of babysitters," she recalls. "But my mum didn't work."

Today, most do: According to the 2010 U.S. Census, in families with a married couple and children under 18, 64 percent had two working parents, up from 33 percent in 1976.

Carl Honoré, a London-based journalist and author of Under Pressure: Rescuing Our Children From the Culture of Hyper-Parenting, says the shift in work patterns makes parents more reluctant to use weekend babysitters.

"There's a lot of guilt, especially in families where both parents are working long hours. That's not something parents should be reproached for. But it's important not to lose mother/father or partner/partner time. If that key relationship falls apart, the whole family unravels."

Anderegg concurs, bluntly: "I don't think there's anything wrong with wanting to spend time with your kids, unless it costs you your marriage."

Add a dash of guilt to a healthy portion of fatigue, stir in some anxiety, and you have Sarah Rosenbaum's recipe for a weekend night spent at home with her husband, Yukio Tezuka, and their 6-year-old son, Ben Yoshi.

Never mind that Rosenbaum, 46, a clinical psychologist, was "the typical teenage babysitter with the ponytail" when she was growing up in Carlisle, Pa. Now, she's not sure a young teen has the "gravitas" to babysit.

"This is the era of the nanny-cam. We're more aware of what can go wrong. Who do you know well enough to let into your home to care for your kids? . . . With a teenager, I'd worry about her judgment in an emergency. If Ben Yoshi pulled a piece of furniture down on himself, or if he was choking . . . I definitely think I worry more than my parents did."

In that, Rosenbaum is not alone. Honoré credits older first-time parents (more likely to overprotect the kids they waited so long to have), smaller families (fewer progeny means more anxiety about their survival), and a feverish news cycle that exaggerates the risk of rare occurrences such as kidnappings by strangers.

"Everybody is marinated in so much worry and anxiety," he says. "Parents may be less willing to let their 14-year-old daughters go babysit, and on the other side, parents are reluctant to leave their kids with an unqualified 14-year-old."

That's why, on a recent Tuesday morning, Red Cross instructor Rachel Rose was coaching a group of future babysitters, five girls and four boys ages 10 to 13. "What's the No. 1 thing, our main responsibility on the job?" she asked. "Safety," they chorused back.

The Red Cross babysitting class, a 61/2-hour curriculum last updated in 2008, covers child care (diapering, feeding, burping), basic first aid, and the business of babysitting. In a sign of more cautious times, instructors advise young babysitters not to post fliers with their names and phone numbers in public places; they tell kids to use word-of-mouth publicity instead.

At the class, held on a teacher in-service day at St. Maximilian Kolbe School in West Chester, Matt Sellers, 12, of Thornton, fumbled a diaper onto a realistic-looking baby doll while 10-year-old Haley Croft of West Chester coached. "Changing a baby's diaper is a lot more confusing than I thought it would be," Matt said, trying to maneuver the doll's plastic feet out of the way.

During the course of the day, the youngsters would discuss peanut allergies and choking hazards. They would debate how to handle various tricky scenarios: What if the parents want to drive you home, but you think they've been drinking? What if you hear gunshots outside the house? What if a stranger comes to the door?

Matt pointed to his 168-page Red Cross babysitting manual. "I had no idea babysitting would be that complicated."

Anika Vaughn-Cooke and Isaac Ewell of Mount Airy found a beautifully simple solution to the babysitting quandary: When they learned, seven years ago, that Vaughn-Cooke was pregnant with twins, they pursuaded Ewell's mother to move from Fayetteville, N.C., to West Oak Lane.

Now she is the default babysitter for Marley and Che, energetic 6-year-olds who like to practice one-handed cartwheels in the living room. The boys have had other babysitters - usually teachers from their former preschool - just four or five times.

"We trust our parents more than we trust someone we don't know," says Vaughn-Cooke, 38. With both grandmothers in attendance, the couple even ventured on an overnight trip when the boys were 3; they flew to Miami at 6 a.m. on a Saturday and returned the next day.

"We recognize that we need that mommy-daddy time," says Ewell, 40, so they have become dedicated to an every-other-Saturday-night date - typically dinner at a restaurant they've read about or seen on the Food Network.

They know other parents who have found creative, low-cost solutions such as babysitting co-ops, informal swaps with neighbors, and, as children get older, sleepovers that give one family a night off.

Vaughn-Cooke considers herself lucky; without her mother-in-law, date night would probably collapse under the combined weight of fatigue, expense, and anxiety. "Our parents are retired, so they can drop everything [to care for the boys]. As you get older, you worry more. You think about all the what-ifs."