A school in Sweden is trying to brighten up the day by fitting special lights into the classrooms.
Sweden is in the north of Europe and in some parts winter can mean long, dark nights and only a few hours of sun each day.
This can affect people in different ways with some saying they don't feel that they have lots of energy.
So a school is trying to tackle this. It's installed lots of special bright lights inside and teachers hope it will improve students' results.
Watch the clip to hear if it's working...