Lights out for people across the Midlands
People across the Midlands will be switching off their lights this eveningin support for action on climate change across the world.
But schools across the region have already been ahead of the game this week, organising events to celebrate their own East Hour.
One of these schools was Rosary Catholic Primary School in Birmingham who were invited to wear green and even did a litter pick.
Pupils also turned off all non-essential lights, computers, printers and other electrical items around the school.
Eco Teacher Mr Perkins said "children held discussions in their classes about climate change and how they can make a difference today so they can have a planet to enjoy in the future."
Herefordshire's Ellie Goulding is also fronting the WWF's campaign and encouraging others to do so using the hashtag #MakeClimateMatter.
The singer said she loves the natural world, and knowing it could be taken away from future generations "just makes me sad".
What is Earth Hour?
The campaign is run by conservation charity WWF
It's been happening for 10 years with the first event staged in Sydney
More than 172 countries and territories taking part
Over 10,400 landmarks and 7,000 cities turning off their lights
People are encouraged to switch off their lights for one hour
Hundreds of millions of people will join the global switch off
It's part of a global movement with over 150 countries taking part
It kicks off at 6.30am GMT in Samoa and rolls through time zones for 24 hours before finishing in the Cooke Islands
In the UK it will take place between 8.30pm and 9.30pm
Businesses, museums and places of worship across the Midlands will also be taking part in Earth Hour tonight in their own ways.
In Birmingham, the Cathedral and Central Mosque will switch off lights and the restaurant, Carters of Moseley, are hosting a candle lit dinner.
A Leicestershire recycling company is also calling for other businesses to follow its lead and turn off all non-essential lighting and appliances.
The company Wastecycle has written to Nottingham City Council, the University of Nottingham and Nottingham Trent University to support it.