Activists are pushing for a strike on Friday 15 February, ahead of a global walkout planned for 15 March.
So far school students have struck in Belgium, Australia, Canada, Germany, Switzerland and Finland under the banner “Fridays for Future”.
The movement is inspired by student Greta Thurnberg, who has been striking every Friday outside the Swedish parliament since September.
Around 12,500 students marched in Brussels on Thursday of last week for the fourth week in a row. One student held a placard reading, “I’ll do my homework when you do yours.”
More than 3,000 scientists have signed an open letter in support of the students. It read, “As scientists, and on the basis of scientific facts, we declare: the climate activists are right!”
They argued that collective action, not just lifestyle changes, are needed to save the planet.
Reballots have opened the way to bigger struggle