Students are expected to once again join nationwide protests as part of an international youth campaign demanding action on climate change.
Organisers behind the Youth Strike 4 Climate movement said "sizeable events" are due to take place in major towns and cities including London, Sheffield, Leeds, Manchester and Brighton.
Demonstrators will take to the streets for the third mass walkout in as many months.
Protests earlier this year have seen police intervening as roads came to a standstill, activists scaled traffic lights and statues, and some sat in front of double-decker buses.
Those going on strike said they are demanding that the Government declares a state of climate emergency, and reforms the curriculum "to address climate change as an educational priority".
They are also campaigning for the voices of young people to be considered when it comes to policy-making and for the voting age to be lowered to 16.
The strikes come in the wake of a UN report which warned that limiting global temperature rises to 1.5C above pre-industrial levels, beyond which climate impacts become increasingly severe, requires unprecedented action.
That includes cutting global carbon dioxide emissions by almost half within 12 years.
Environment Secretary Michael Gove has previously spoken of his support for strikes, saying: "Collective action of the kind you're championing can make a difference, and a profound one."
