The science is crying out for urgent action, and still our leaders dare to ignore it. So we continue to fight.

After a year of strikes, our voices are being heard. We are being invited to speak in the corridors of power. At the UN, we addressed a room filled with world leaders. At the World Economic Forum in Davos, we met with prime ministers, presidents, and even the pope. We have spent hundreds of hours participating in panels and speaking with journalists and filmmakers. We have been offered awards for our activism.

Our efforts have helped to shift the wider conversation on climate change. People now increasingly discuss the crisis we face, not in whispers or as an afterthought, but publicly and with a sense of urgency. Polls confirm changing perceptions. One recent survey showed that, in seven of the eight countries included, climate breakdown is considered to be the most important issue facing the world. Another confirmed that schoolchildren have led the way in raising awareness.

With public opinion shifting, world leaders, too, say that they have heard us. They say that they agree with our demand for urgent action to tackle the climate crisis. But they do nothing. As they head to Madrid for the 25th session of the Conference of the Parties (COP25) to the UN Framework Convention on Climate Change, we call out this hypocrisy.

On the next two Fridays, we will again take to the streets: worldwide on November 29, and in Madrid, Santiago, and many other places on December 6 during the UN climate conference. Schoolchildren, young people, and adults all over the world will stand together, demanding that our leaders take action - not because we want them to, but because the science demands it.

That action must be powerful and wide-ranging. After all, the climate crisis is not just about the environment. It is a crisis of human rights, of justice, and of political will. Colonial, racist, and patriarchal systems of oppression have created and fueled it. We need to dismantle them all. Our political leaders can no longer shirk their responsibilities.

Some say that the Madrid conference is not very important; the big decisions will be made at COP26 in Glasgow next year. We disagree. As the science makes clear, we don't have a single day to lose.

We have learned that, if we do not step up, nobody will. So we will keep up a steady drumbeat of strikes, protests, and other actions. We will become louder and louder. We will do whatever it takes to persuade our leaders to unite behind science so clear that even children understand it.

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