“It’s a movement, not a moment.” That’s the mantra from Sam “Coach” Balto, a former school teacher from Portland, Oregon who quit his day job to stoke a revolution called the “bike bus” – groups of kids and families cycling to school together.

How did one person in a mid-sized American city turn a weekly bike ride into something of a phenomenon? He leaned on the power of social media. In the past two years his videos have been viewed by hundreds of millions of people.

Riding bikes to school shouldn’t be a big deal, but it nearly became extinct in the US after decades of helicopter parenting, automobile-oriented cities and the epidemic of dangerous and toxic car traffic that accompanies them.

Like a scientist restoring a threatened species, Balto turned his passion for the benefits of physical activity in young people into a trend that has gone from his current home town in the Pacific north-west to the White House in Washington DC (where he was invited by former president Joe Biden to attend a holiday reception), and beyond. Today, Balto estimates there are more than 200 bike buses across the US.

They have been around for a while. In Portland, a “bike train” movement kicked off in 2010 when a 24-year-old bike advocate named Kiel Johnson began organising what he referred to as “bike trains” at an elementary school, where riders would join a mass of cyclists at various stops along a route to school. It caught on and in just a few months Johnson had signed up six other schools, won a grant, and had been interviewed by a national television show.

He also used Facebook to spread information and communicate with other bike train leaders but video – other than one uploaded to YouTube in 2010 that barely reached 1,000 total views – wasn’t part of the picture. “When you joined one of the big bike trains it really felt like you were part of something – we just didn’t have a way to share that,” Johnson recalls now. “Social media didn’t have that ability back then.”

It would be another few years before sharing videos on Vine, TikTok and X (then Twitter) would become mainstream. That Johnson found success without the boost of social media, however, showed the viral potential of the bike bus. It also proved to be a challenge, because without viral videos to reach and inspire millions in minutes, Johnson had to do a lot of that work himself. That lack of scalability was one reason he wasn’t able to keep pushing bike trains forward. In 2012, two years after they started, the bike train movement had reached the end of the line.

But great ideas have a way of staying alive. Nearly a decade later, while on a trip to Spain, a Californian called Zach Klein came across a large group of schoolchildren riding through the streets of Barcelona and took a video. “Something special is happening in Barcelona,” he posted on X on 18 October 2021. “They call it Bicibús – or Bike Bus.” Klein’s post went viral and was picked up four days later by National Public Radio, and then spread online like wildfire. One who saw it was Balto.

The following spring, Balto, then a physical education teacher at an elementary school, recalled that bicibús video from Spain and decided to try one of his own. He hatched a plan for a “Bike Bus for Earth Day” – a group ride that would meet about a mile away from school and pick up children and parents on bikes along the way.

“I think this is the start of something really special here,” Balto said from the start of the ride that morning. Turns out that was a massive understatement. The children loved it, and why wouldn’t they? The benefits, after all, of cycling regularly are vast. It’s good for children’s health – mental and physical – and also has a ripple effect of advantages for the whole family, as any Dutch person will argue. Many of Balto’s students say the best thing about the bike bus is that it’s simply a cool thing to do with friends.

But the excitement went way beyond the school. Not only did the students excitedly demand to ride again the following week, but videos went viral beyond anything Balto could have imagined. When he posted his first clip of the Earth Day bike bus on 22 April 2022, it was watched more than 200,000 times. And that was just the beginning.

In September 2022, one of his bike bus videos got more than 1m views on TikTok. A week later, a parent posted a video of the bike bus that got more than 2m views overnight. Balto recalls looking at his phone that next morning and yelling: “Holy shit! Holy shit!” to himself. That same day he received emails from NBC, CBS, Access Hollywood and other media outlets.

Over the next three years, Balto went from quirky Portland bike activist to a bona fide internet celebrity. Last month, Justin Timberlake joined his bike bus after giving in to prodding by Balto and his legions of followers on TikTok and Instagram. Timberlake was performing that night and showed up beforehand to pedal alongside Balto and hundreds of kids and fans. The video of that ride has 3.2m views. In the past year alone, Balto’s videos have been viewed more than 200m times.

Balto, who now runs the nonprofit Bike Bus World, credits social media for building the movement. “Without it, this might have remained just a cool local initiative in Barcelona. But social media made it global. The visibility also helped change public perception about kids biking to school, proving that it’s fun, safe, and scalable.”

Balto is right that moments are not movements, but as long as moments can be captured and shared on social media, sometimes movements will follow.