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Pupils light up Christmas tree
Everyone knows Christmas lights use LOADS of electricity, but now a village primary school has come up with a green way of making it - pupil pedal power!
By pedalling away on exercise bikes linked to battery packs, pupils at the school near Stranraer, in Scotland, can create up to 150 hours of electricty.
That's enough to power all of their school's Christmas lights.
It's all part of a project by inventor Antony Berretti to teach kids about maths, physics and the environment.
Pupils can create up to 150 hours of electricity on the recycled bikes
He came up with the idea after hearing a news story about the increased demand for electricity over the festive season.
"We hope this will allow children to understand the nuts and bolts of energy production and its wider impact on the environment and what can be done to reduce it," he said.
If the project continues to be a success, Mr Berretti thinks it could eventually be used by other schools too, to power things like computers and printers!