Suvita Melehy, who practices law in Silver Spring, Maryland, has mastered the art of moving her kids around, using a combination of carpooling, trading favors, reducing her work hours and researching bus schedules to ferry her two daughters, 16 and 13, from school to a host of activities.

"After school is a logistical nightmare," she said. The girls attend Stone Ridge School of the Sacred Heart in Bethesda, Maryland, tennis team practices are in College Park, Maryland, and guitar lessons are at the School of Rock in Silver Spring. "And traffic in this area is so horrendous, it only makes things worse."

At her wit's end when arrangements fell through a few months ago, Melehy tried something new: She called Uber.

Families with less means often rely on public transportation or extended family to get their children around, with many immigrant families turning to "raiteros," or cheap, informal car and van networks. But for affluent parents who can pay to ease the pressures of juggling work and family and are jittery about leaving children completely to their own devices, Uber and other app-based car services have clear appeal.

"It's cheaper. It's on-demand, so you only use it when you need it, as opposed to reserving somebody," Melehy said. "Uber is just another tool for families to make it work."

Perceiving a new market, similar services are cropping up around the country, including Little Angels Transportation in Rockville, Maryland, Kangaroo Coach in Baltimore and Mom's Taxi Service in Florida. Shuddle, an on-demand child transportation service that's booming in the San Francisco Bay area, specializes in hauling kids as young as 7 around.

But while Uber is reaping profits from transporting unaccompanied children, it isn't designed to. Despite the recent launch of UberFamily, which allows parents to order cars equipped with car seats and provides tablets for entertainment, the company's terms and conditions state that individuals under 18 are not permitted to use the service if they're not riding with an adult. Minors are also prohibited from opening accounts.

Uber spokesman Taylor Bennett said the company had no comment on the fact that a growing number of teens and tweens across the country are using the service.

Many parents interviewed — who said they had no idea about the ban on kids under 18 — say they prefer Uber to cabs, which cost a little more or a little less depending on the type of Uber service. Parents say the combination of easy pick up, easy payment (automatically by credit card) and the ability to track vehicles via GPS through the app gives them a sense of control, efficiency and security they don't feel they have with traditional taxis.

Pam McGonigal, who began using Uber last year to ferry her 14-year-old daughter from dance class in Silver Spring, back home to Chevy Chase, Maryland, when she got stuck at work in Washington, said she had never considered a taxi for the job.

"I just have reservations about my pretty little girl going out and hailing a cab," she said.

But Uber's competitors question whether that trust is misplaced.

Dave Sutton, spokesman for the Rockville-based Taxicab, Limousine & Paratransit Association, noted that officials in Los Angeles and San Francisco have questioned the company's methods for screening drivers. He said unlike the taxi industry, Uber's background checks don't include fingerprinting. Uber officials said the company does not use fingerprinting as part of its background checks, but said they think the process they use is more comprehensive.

"Obviously, everybody loves their kids, but the idea of placing a young person with someone who hasn't received a criminal background check is terrifying," Sutton said. "We're working to make sure that people understand that."

Like anything when it comes to parenting, the practice isn't without its critics.

Brian Solis, a senior analyst with Altimeter Group, a San Mateo, California-based company that examines the impact of new technologies, sees both sides. While he's comfortable using Uber to transport his teenage son and stepdaughter to their various activities and social engagements, his wife is less sanguine. She worries about their safety given past reports of assaults involving Uber drivers, not to mention what others might think about what using Uber says about them as parents, he said, for not making sacrifices to drive their own kids around.

Still, he argues that the service enables members of his family to do more of the activities they want to do both together and apart. Before, if his stepdaughter wanted to meet up with friends but neither parent was able to drive her, she wasn't able to go. Now they have an option.

San Francisco-based Shuddle, which launched in October, specializes in after-school transportation. The company predominantly hires women — caregivers, teachers, nannies and stay-at-home moms looking to pick up extra cash. They are screened and trained to go into buildings, meet with teachers and other adults, and sign kids in and out of school, sign in at orthodontist appointments and take children right in to Scout meetings and other activities.

Chief executive Nick Allen, a veteran of Sidecar, another app-based transportation service, seized on the idea after getting calls from drivers that parents were putting their 12-year-olds into the cars.

"Parents are busier than ever these days. Both moms and dads are working, kids have activities all over town, and parents can't be in two places at once," Allen said. "This is giving kids independence and parents breathing room to have a better quality of life."

Since its debut last fall, Shuddle has tripled in size, Allen said, and is in the planning stages of going nationwide.

Debbie Landa, who works for her family's business in Alexandria, Virginia, said she and her husband turned to Uber to get some sanity at home. After years of taking their son, Sam, from Alexandria across town in rush hour to the Washington School of Ballet for classes five days a week — and weekends for rehearsals — Landa said she had a breakdown. Now, the family lets Sam, 15, use Uber once a week. "And we get to have dinner at a decent hour with our older son for once," she said.

For those with means, it's not just kids with places to go who are taking advantage of Uber. Some parents have used the service to ensure the teenage babysitters they employ get home safely.

Bereket Selassie, a real estate developer, said he and his family started using Uber because it can be hard to hail a cab near his home in Southeast Washington. He said it can make for a more relaxed night out since they know they have another option for getting the babysitter home.

"It's just comforting to know I can track it and if something, God forbid, does go wrong, we'll be able to see that," he said. "When you're trying to get an 18-year-old back to her family — it's just something that just made us feel much more secure."

That parents are seizing on app-based services to manage their busy lives comes as no surprise to Liana Sayer, a sociologist at the University of Maryland who studies how families spend their time. She said surveys show that American children are spending more time on leisure activities. And American parents, particularly middle-class mothers, are spending more time with their children than ever before, running themselves ragged trying to haul kids around just like stay-at-home mothers in previous generations did.

"So it's not surprising that parents with resources are turning to new technologies, like Uber, to ease time crunches," Sandra Hofferth, a professor in the Department of Family Science at the University of Maryland said. "And maybe it's even less surprising in an area like D.C., where most of us would avoid getting into traffic to the extent that it's possible."

Still, despite the convenience, the breathing room and the sense of relief Karla Harr, a lawyer who recently returned to full-time hours, using Uber to get her teenage daughter to ballet classes everyday, she mourns having to outsource one more aspect of family life.

"There is a point in having those precious moments, even if they're chaotic, driving from one place to the next event," she said. "You still have those minutes of connection and conversation, even for a little while, before the earbuds go in."