Thousands of students poured out of schools across Europe on Friday. They waved posters and carried banners as they marched in a co-ordinated strip to demand action against climate change.
In London, the students sang: " Save our planet! "gathered on Parliament Square, where traffic came to a standstill. Others held signs saying "Change politics, not the climate."
Around 200 students gathered in front of the Ministry of the Environment in Paris, saying they hoped to repeat the demonstration every week until their demands were heard. They called on the government to cut France's greenhouse gas emissions by at least 4 percent a year.
Inspired by her, a movement known as youth, Strike 4 Climate was founded in the UK and has grown rapidly since 1945, fueled by social media. Demonstrations took place in Belgium, Great Britain, France, Germany, Ireland, Sweden, Switzerland and other countries.
Luisa Neubauer, 22, one of the organizers of the weekly marches in Berlin, described the demonstrations on Friday as powerful. Children at the age of six came out to university students, she said.
"I'm convinced we can actually make a difference during these strikes," she said.
While Some Politicians Supported The Students, Others, including Prime Minister Theresa May of the UK, were skeptical.
A spokeswoman for Ms. May said, "Everyone wants young people to engage with the issues that affect them the most, so that we can build a brighter building for all of us. However, it is important to stress that interruption increases the workload of teachers and wastes teaching time, which teachers have carefully prepared for. "
The Prime Minister's response has been criticized by some, including Ms. Thunberg, the Swedish teenager.
PM says children who have striked at school are "wasting class time". That may well be the case. Ms. Thunberg wrote on Twitter . "On the other hand, political leaders have wasted 30 years of inaction, and that's a bit worse."