Here's a fact that should smart a little: Peer pressure to have a cellphone is reaching younger and younger consumers. A study from Influence Central found that the average age of a first smartphone user is 10, down from 12 in 2012.

Of course we could just say no to our progeny, but who do you think we are — our parents? That generation of authoritarian moms and dads had no trouble with the word, comfortably united as the Boss of Us and at the ready with the world's most famous rhetorical question:

"If all your friends jumped off a bridge, would you jump, too?"

But they didn't have smartphones to contend with. We're addicted to them, so it's no surprise that our kids can't detach, either. That leaves us grateful for the benefits of this remarkable technology, and worried about risks — to our kids' sleep, social and academic skills, and overall sense of self-worth. We need help.

Which has arrived.

A grass-roots group based in Austin, Texas, and with a Minnesota presence is trying something bold: A campaign called Wait Until 8th.

Their simple goal: Hold off on giving kids smartphones until they're in eighth grade. Flip phones for texting and calling are fine.

The best part for parents likely to cave: Your pledge becomes active only when 10 or more families from a grade at the same school have signed it.

"That's to empower people to do it and not worry, 'What if I'm the only one?' " said Wait Until 8th founder Brooke Shannon.

"We need to put boundaries in place. We need to exert authority. But there is strength in numbers."

Parents in all 50 states, more than 8,500 in all, have signed up, said Shannon, who has 5-, 9- and 10-year-old daughters.

That number will only grow. In February, Common Sense Media and SurveyMonkey released a study revealing that 47 percent of parents worry that their children are addicted to their mobile device.

Concerns range from access to inappropriate videos, to bullying, to something more nostalgic: the loss of childhood.

"They're not reading books, playing outside with neighbor kids, riding a bike," Shannon said. "Instead, it's hours and hours on YouTube, and wondering why you weren't invited to the sleepover. Hours of Snapchatting and looking at memes, and really just missing out on being a kid.

"My hope is that, eventually, this will change the average age a child does get a smartphone," she said. "It's four more years free from that distraction."

It's not just grown-ups who are taking note.

Ciara Kinney is a seventh-grader at Olson Middle School in Bloomington. While not having a smartphone "is definitely my parents' idea," she appreciates their reason for holding off.

"I clearly want one, but I see why I'm not getting one, and I'm kind of glad. Before people get their phone, they do more stuff; then, they mostly spend time on Snapchat."

Malik, 17, whose supervisor at Cookie Cart in north Minneapolis asked that just his first name be used, got his first smartphone at 14. "I know I get distracted with the apps, like Facebook, Snapchat and Instagram," he said. He puts his phone in his book bag to get away from it.

His co-worker Zuri, who is 15, points to another concern around connection.

"I was bullied," she said, beginning in school, but quickly migrating to cyberspace. "I had to learn, when do you turn it off? If you have a problem with me, I'd rather you'd say it to me. But no one really does."

Shannon, who worked in public relations and marketing, shifted to this passion project full-time about a year and a half ago.

"We live in an affluent community, and because of that, there's a lot of gadgets," she said. "There are first-graders with smartphones — we're talking about the latest edition."

Driving past the local middle school, she also saw that "nobody was talking to each other. Everybody was completely entranced with their smartphones." She wondered: How can it be different?

Shannon sent an e-mail to 20 moms, asking about phones with their own kids. Some said they were planning to wait. Others wanted to wait, but said "the pressures became too much."

So Shannon created a website — ­waituntil8th.org — and launched it a year ago. Parents quickly signed up. "It is just resonating with so many parents."

She acknowledges the benefits of a smartphone, keeping kids current on news and music, and even getting homework updates.

"But the consequences of having one far outweigh not having one," she said. "A basic phone where you can call and text, that's all kids need."

Sarah Kallal of Eden Prairie signed the pledge as a stay-at-home mom of four children age 7 and under. Her husband, Simon, also is on board.

"I'm on the extra-preventative side right now," Sarah Kallal said. "You hear about all the cyberbullying and sexting. It is crazy. Once kids get a phone, it makes life so much harder. It's just one more thing to monitor."

Kallal passed on the information about Wait Until 8th "to a bunch of mom friends … and it's starting to spread like wildfire."

Katie Hanson, 36, of Bricelyn, Minn., is mom to girls ages 5, 7 and 9. She and her husband, Alan, also signed the pledge.

Like Kallal, she appreciates the challenges of saying no. Her family moved from Robbinsdale to Bricelyn, population 350, two years ago, and Hanson relies heavily on technology in her work for a corporate real estate firm.

"We're working so hard to keep our girls, not away from it, but not saturated by it," she said, noting that one reason for the move was to "get outside."

She added, "They have their whole lives to be glued to their phones. They're only a kid once."

Her oldest daughter will be in fifth grade next year, but Hanson has told her, "Don't be asking for a phone."

"They need to have a reason for things," Hanson said of her girls. "Build a case for us for why you think you need this. She understands there's no real reason for it."

gail.rosenblum@startribune.com 612-673-7350 • Twitter: @grosenblum