She's only 16 but Greta Thunberg has sparked a global movement.
It's seen hundreds of thousands of schoolchildren walking out of lessons and picking up placards, all in the name of the planet.
(SOUNDBITE) (English) SWEDISH CLIMATE CAMPAIGNER GRETA THUNBERG, SAYING: "My name is Greta Thunberg, I am 16-years old and I am from Sweden and every Friday I am school striking for the climate outside the Swedish parliament alongside hundreds of thousands of other children from all around the world." It all began last August when the Swedish activist was just 15 and she began skipping Friday lessons to strike outside Stockholm's parliament.
Since then, many have taken her cue, from Germany, to the UK, to Australia, all calling for more action to tackle climate change.
(SOUNDBITE) (English) SWEDISH CLIMATE CAMPAIGNER GRETA THUNBERG, SAYING "I don't think I've started a movement.
I just think that I did an action in a time where more and more people are starting to become more aware of the situation we are in and then kind of show people the method you can use to make your voice heard on this." It's a movement that's already seeing results.
Last month Thunberg won a European Union pledge to spend billions combating climate change over the next decade.
(SOUNDBITE) (English) SWEDISH CLIMATE CAMPAIGNER GRETA THUNBERG, SAYING: This takes up a big part of my life now (...) I will continue to strike every Friday until Sweden is in line with the Paris agreement.
But that may take a couple of years, I will just have to try and be patient." Youth organizations are calling for an unprecedented strike this week, in which students from 40 countries are expected to participate.