London (CNN) Anna Taylor tapped on her smartphone from the sidelines of a climate change protest on a sunny February afternoon in east London. Bundled in a green waterproof jacket, she tried to catch up with scores of WhatsApp messages from working groups seeking her direction on an upcoming strike.

A thick smudge of gold glitter on her right cheek belied the fact that Taylor, 17, has taken a leading role in organizing a protest that is expected to see hundreds of students walk out of class across the UK on Friday.

The school walkout, called Youth Strike 4 Climate, is planned for more than 40 British towns and cities. Its aim, Taylor said, is to raise awareness of the threats of climate change. "It has felt like a full-time job on top of school work," she said of balancing final year exam revision with activism. "I don't have time to see my friends as much anymore ... [nor] am I getting much sleep."

Taylor and co-organizer Vivien "Ivi" Hohmann are almost certain to get a detention for protesting on Friday, and not everyone sees altruism behind their actions. "I had an interview a couple of weeks ago and the journalist kept saying: 'you are just playing truant -- that is what you are really doing,'" Taylor told CNN.

On Sunday, the British tabloid Daily Mail questioned whether the walkout was student-run, suggesting that it had "been hijacked by hardline climate groups and career activists."

This was Taylor's first taste of the skepticism that has met a growing ecosystem of student-led climate strikes, which are crisscrossing Europe and Australia, many of which are being conceived, organized and executed by teenage girls.

And Taylor said Friday's event is only a warmup for a worldwide student strike on March 15.

Global movement inspired by Swedish teen

In Australia, around 15,000 students took to the streets in November after Harriet O'Shea Carre and Milou Albrecht, both 14, wrote a letter calling for greater action on climate change.

In Belgium, a student-led climate march, started by schoolgirl Anuna De Wever and her best friend Kyra Gantois, saw more than 10,000 people hit the streets across the country during its fifth iteration last Thursday. Their January 24 march saw a turnout of 35,000, Belgian police said.

Students gather at a climate change event in Sydney.

All of the organizers point to the diminutive pigtail-toting Swedish climate activist Greta Thunberg as their inspiration. The 16-year-old took the world by storm last year with her weekly sit-ins outside Sweden's Parliament. Thunberg said she won't stop until the country is in line with the Paris Agreement, an accord that aims to limit a global temperature rise this century to 1.5 degrees Celsius.

Her rising star got her an invite to Davos, which Thunberg took a 32-hour train to from her home in Sweden. Once there, she excoriated a room full of executives, telling them they were to blame for the climate crisis.

"I told them that they belong to that group of people who are most responsible and that the future of humankind rests in their hands, and they didn't know how to react," she told CNN in January.

Thunberg's iron-willed actions have led to critics alleging that she is manipulated by her parents, or is the mouthpiece of an environmental PR campaign. She took these claims to task in a February Facebook post: "Many people love to spread rumors saying that I have people 'behind me' or that I'm being 'paid' or 'used' to do what I'm doing. But there is no one 'behind' me except for myself," she wrote. "I am not part of any organization. I sometimes support and cooperate with several NGOs that work with the climate and environment."

Recently I've seen many rumors and lies circulating about me. And enormous amounts of hate.

So I've written a text to make some things clear about my school strike. #climatestrike #fridaysforfuture #schoolstrike4climate https://t.co/4jsklH2PaJ pic.twitter.com/tiGCULIJST — Greta Thunberg (@GretaThunberg) February 2, 2019

'People find it hard to imagine young women with power'

De Wever told CNN that conspiracy theories, death threats and the occasional jibe on the street have not taken the shine off her strikes in Belgium. False claims against her marches also led to the resignation of an environment minister, who incorrectly said the country's intelligence service had evidence that unnamed powers were behind the protests. "She lied," De Wever said bluntly. "So she was fired."

The conspiracy theories against De Wever have caught the attention of Maarten Schenk, co-founder of Lead Stories, a site that debunks viral hoaxes and is one of Facebook's fact-checking partners. "There is an image floating around social media here [in Belgium] trying to connect the various people involved in the climate marches, [incorrectly] pointing out connections to various trade unions and political parties on the left," he told CNN.

Thunberg strikes every Friday outside Swedish Parliament in a bid to get politicians to act on climate change.

De Wever's mother, Katrien Van der Heyden, who is a sociologist and owns a consultancy firm, has also been a target, said Schenk. He has received a number of emails sent in from conspiracy theorists purporting to show Van der Heyden's "secret links" to Belgium's Green Party, Groen -- which is untrue.

"There is something going on here where people find it hard to imagine young women with power," Van der Heyden told CNN about the false rumors swirling around her daughter's movement. "They think there must be some adult males behind the scenes pulling the strings."

De Wever thinks the disbelief stems from an ingrained patriarchal attitude in society, where people find it hard to believe that young women can't inspire and run their own movements. "And I think that is an insult," she said.

How to start a movement

Getting people to out to protest is not rocket science, according to De Wever. Her campaign to get Belgian school children striking began with a video post in December, which she said then went viral . The campaign has since scaled up with Instagram and Twitter accounts, and plans for an online platform.

While De Wever plays the public-facing role, she said Gantois is "the organizer" who informs authorities of upcoming protests and manages "much of the agenda." The girls meet up once a week with a core organizing committee of around 10 other students.

De Wever (center) is the public face of the strikes in Belgium.

The campaign hopes to put climate change on the political agenda in both the upcoming European Parliament and Belgian elections.

"With these strikes I want to say look, you are just sh***ing on children's futures," De Wever said, referring to the government's failure to take more ambitious steps to limit climate change during United Nations talks in December.

The internet as a catalyst

Meanwhile, Anna Taylor, who said she conceived the UK movement with two friends, said the support she has received from major environmental groups has been kept to a minimum. They plan on borrowing audio speakers from Greenpeace for Friday's march and are getting legal training from environmental group Green & Black Cross.

She said that student working groups, coordinated on WhatsApp, do the bulk of logistical work, including weekly video conferences where up to 40 young people dial in to "work through the agenda, press, social media, fliers and art work, website and demands." They also received money from a crowdfunding campaign to build a website.

What skeptics don't understand is "the extent to which social media has transformed the way young people connect," said Christopher Rootes, a University of Kent professor who studies green protest movements. "I suspect that any funding from external environment groups is minimal and that coordination is via social media -- and friendship groups," Rootes added.

He said that some parallels can be drawn to when the New Yorker began publishing a series of essays from naturist Rachel Carson's 1962 book "Silent Spring," which warned Americans of the dangers of unbridled pesticide use. Her chronicle grew into an environmental movement in the US -- quite like the actions of a girl outside Swedish Parliament, according to Rootes.

While Greta Thunberg's protest had the power to spread much faster thanks to the internet, Rootes "suspects the shelf life" of contemporary, viral movements might also be "much shorter."

As other issues consume the attention of UK lawmakers -- not least Britain's pending withdrawal from the European Union -- could Friday's march be at risk of being ignored? "Now is time to hold the protests because the government is focused on the economy and housing prices and stuff -- environment policy is low on their priority list," Taylor said. "Politicians are too concerned with hard or soft Brexit and are forgetting the Earth is dying."

If not politicians, Taylor is hopeful that other young people will be inspired by the strike. "For so many years I was passionate about the environment, but I did not know anyone else," Taylor said.

"I thought I was the only one worried about the planet and then, suddenly, there are other kids taking the chance to change things -- and I am sure it will empower other kids to do the same."