Xiuhtezcatl Roske-Martinez was 6 years old when he gave his first moving speech.

Let me guess: You're expecting an adorable lecture on "Spongebob Squarepants" or something, right?

Nope. When the young Xiuhtezcatl (pronounced kind of like "shu-TEZ-cuht" in my embarrassing English phonetic approximation of the Nahuatl language) addressed that crowd of 200 people in Boulder, Colorado, cartoons weren't on his mind.

"I got up on stage ... and delivered a message about how we gotta educate kids differently and parents have to raise us differently to understand that it's important to take care of the planet," he tells Upworthy.

6-year-old Xiuhtezcatl speaking truth to power. GIF via tamaragaya/YouTube.

That's right: While most kids his age were still trying to figure out whether Santa Claus is real, Xiuhtezcatl was out saving the world.

That was 2007, and the then-6-year-old had just seen "The 11th Hour," a documentary about global warming produced and narrated by Leonardo DiCaprio. "It was intense, it was like a total wake-up call. I was like 'Mom, I gotta talk to people, I gotta speak,'" he said.

Xiuhtezcatl didn't stop there. He could have settled with his 15 minutes of fame — but he built an army instead.

As a young teen, Xiuhtezcatl began to organize his friends into local action committees to get pesticides out of parks as well as enact bans and other regulations on plastic bags, coal-ash drilling, hydraulic fracturing, and other unsustainable practices that had taken over the Boulder community he calls home.

"I had a lot of friends that I knew who were interested in this kind of stuff, that didn't really have a platform to engage," he explains. "And that's what you'll find all over the world."

With the help of his activist parents, Xiuhtezcatl created a nonprofit organization called the Earth Guardians, a self-described tribe of young activists, artists, musicians, and leaders.

"It started off as a simple little thing in our community, you know, just us kids," he explained. "And then all of a sudden social media got a hold of us and now we have 400 crews on 6 continents and it's a global movement."

Since then, Xiuhtezcatl has hung out with Pharrell Williams and been featured in Rolling Stone. He's also addressed the entire United Nations about climate action (we spoke to him back then, too) and, oh yeah, sued the U.S. government over the same.

Not slowing down, this guy. In fact, when I spoke to him during the 2015 Conference of the Parties in Paris, he had to cut our conversation short to go perform a concert for the United Nations at the Grand Palais.

Oh yeah — did I mention that he's also a bomb-ass hip-hop artist?

When I asked him about his music career and the beats he's dropped with his younger brother Itzcuauhtli, Xiuhtezcatl and his friend started to stomp the floor in unison, claps slowly building on the offbeats as they chanted, "We got knowledge / and power / and justifiable rage / we know history / and this is me / writing a new page."

Xiuhtezcatl is no stranger to the power of protest songs.

He witnessed their effectiveness firsthand when he and Itzcuauhtli were performing at the Arise Music Festival in Boulder:

"This guy came up to me afterward and he was talking about how he has 400 acres of land, huge property. He was going to lease it all to the oil and gas industry, on his land. And he says, 'After I saw your performance, I realized that, you know, my role in this movement is to build a hub and a place for solutions, not sell it out to the industry for corporate dollars.' So he converted it into a total sustainable hemp farm to help build and create local solutions."

Xiuhtezcatl is as media savvy as you might expect from someone dubbed the "Anti-Bieber." But when he tells this story, he starts to shake his head, as if he's still in disbelief of his own impact. "It was really exciting to see how us educating people on the stage changes people's minds about a huge decision," he said, in a rare moment where he sounds less like a wizened climate warrior and more like, well, a 15-year-old kid grappling with the true scope of the world.

"That's 400 acres of land," he said. "I mean, how many fracking wells can go on there? How many thousands of barrels of oil and natural gas was not pumped because of that decision? It was cool."

Xiuhtezcatl has already accomplished some amazing things — and we can't wait to see what his future has in store.

Let's make sure there's still an Earth for him and his crew to keep on guarding.

Here are some closing thoughts from Xiuhtezcatl himself, straight from this year's Earth to Paris event in December: