As Greta Thunberg walked on stage to cap Friday’s climate strike in downtown Denver, the kids and adults in the crowd buzzed with excitement, craning their necks to see the 16-year-old Swede who battles the American president on Twitter and is inspiring a generation of young climate activists.

Thunberg took the microphone, prompting screams of “We love you, Greta!” from the far reaches of Civic Center’s Greek Amphitheatre. She looked out at the eager activists and inspired teens, many holding signs emblazoned with her face.

“This is real hope, what we’re seeing right now,” Thunberg told the crowd of children and parents, teachers and indigenous leaders. “This is the hope — the people.”

Indigenous communities of CO helped organize today’s strike. “Stand and protect all things Mother Earth” Ken Frost said. “We have been the caretakers of the land since the beginning of time” pic.twitter.com/ICpyc3j9e7 — Sam Tabachnik (@sam_tabachnik) October 11, 2019

Thunberg’s fiery remarks last month during a United Nations climate change conference made her an international hero and a lightning rod for critics. On Friday, she headlined the Denver climate strike that brought together youth activists — including many from Colorado’s indigenous and marginalized communities — to add urgency to the fight against climate change and to put pressure on political leaders to take the issue more seriously.

The strike stems from Thunberg’s “Fridays for Future” protests, which began in August 2018 after she sat outside the Swedish parliament to protest the lack of action on climate change. Thunberg’s strikes prompted youths from more than 100 countries to take up the pledge to protest outside the halls of power in their respective cities and towns.

“This is a movement with millions upon millions of people telling world leaders to act on the science, and we are demanding a safe future for everyone,” Thunberg said. “And that is not something you can continue to ignore.”

World leaders, she said, are failing their constituents.

“It should not be up to us to take the responsibility,” she said. “But since the leaders are behaving like children, we have no other choice.”

After her climate protests captured the attention of millions around the world, Thunberg was nominated — and considered a favorite — to win the Nobel Peace Prize. On Friday, the Nobel committee awarded the prestigious prize to Ethiopian Prime Minister Abiy Ahmed.

Her emotional speech at the U.N. excoriating world leaders for their inaction on climate issues went viral, and President Donald Trump’s mocking of Thunberg on Twitter helped turn the Swedish teen into a household name.

Julia Witteman, a junior at the University of Colorado Boulder, said she came to strike Friday because political leaders have not viewed climate issues as urgent. And she came away inspired by the 16-year-old who has become the mouthpiece for a generation.

“I like that she just gets to the point,” Witteman said. “She’s the leader we needed.”

Students such as Mina Doeble left classrooms to join the protest. Mina, who attends Merrill Middle School in Denver, brought a sign that read, “I’ll stop skipping school when you stop skipping the climate pact.”

“Our generation is being affected by climate change, so we’re the ones that have to live with it,” the seventh-grader said, adding, “Greta Thunberg is awesome.”

Friday’s event also featured traditional Ute songs and incense burnings, along with chants and pleadings, as tribal members young and old reminded those in attendance that their communities are often on the front lines of a changing climate.

Many of the presenters had red and black hands painted on their faces, an ode to the missing and murdered indigenous, black and migrant women and children.

A panel of youth activists spoke about the need to support political leaders who back the Green New Deal; the need to pressure state lawmakers to ban single-use plastic bottles; the need to bring the indigenous community to the table when their issues are at stake.

The crowd featured an array of signs, including several that said “How dare you!” with Thunberg’s face — an ode to one of her go-to phrases that she repeated Friday to thunderous cheers.

As she paused, chants of “How dare they!” emanated throughout the amphitheater.

“We will do this every Friday for as long as it takes,” Thunberg said. “We are rising. We will not back down.”

Updated 5:15 p.m. Oct. 11, 2019 This story has been updated to correct the spelling of Mina Doeble’s name.