Thousands of students in Europe are expected to skip the lesson and call for climate change.
Children plan to host a town hall in front of the town hall in Basel in Switzerland, and similar protests are planned in Berlin and other German cities.
They are inspired by 1
On Thursday, 35,000 young people marched against global warming in Brussels.
Thousands of students are on strike in Switzerland a week ago calling for climate protection.
In Brussels, where the main EU institutions were located, the students wore banners bearing slogans such as "Dinosaurs believed they had time" and "Be part of the solution, not pollution."
German students mobilize with the Twitter hashtag #FridaysForFuture .
Young activists urge world leaders and corporate leaders to meet the ambitious climate change goals agreed in 2015 in Paris. 19659014] What is in the Paris Climate Agreement?
What is the message of Greta?
Every Friday since August Greta Thunberg sits in front of the Swedish parliament to convey her climate message.
She took the train all the way from Sweden to Davos by train, which took 32 hours. This underlines the need for clean transport. Jets emit particularly high amounts of CO2.
She has voiced some criticisms in social media: some accuse her of encouraging truants, inspire the public, and do the work of environmental lobbyists.
But one of her young German followers, Jakob Blasel, said that combating climate change is "more important to us than education".
"Why should we study if we have no future?" he asked.
In the Swiss ski resort, Ms. Thunberg told business leaders, "Some people, some companies, some decision-makers in particular knew exactly what invaluable assets they sacrificed to continue making unimaginable sums of money … and I think many of you today belong to this group of people. "
She later spoke to the BBC:" My message was that most emissions from a few people, to the very rich people who are here in Davos. "
She said her criticism sparked some nervous laughter and applause from the rich and powerful gathered there. Many of them flew private jets to Davos.
"These people have a lot of power, they could really change something, so I think they have a big responsibility, they have to set aside their economic goals to secure the living conditions," she told the BBC
Sie also said Sweden is "not a role model – it is one of the ten countries with the highest environmental footprints per capita."