ECO-friendly schoolchildren had a ball yesterday as they celebrated National Walk to School Week.

Children at Witton-le-Wear Primary School kicked 70 penalties against school mascot, Sam, to help them understand the amount of pollution caused when parents drive them to school.

An average school run produces the amount of carbon dioxide that would fill 70 footballs. An inflatable globe holding the same volume was also on show.

The travel plan was devised between the school and Durham County Council's travel planning team. The school has proven how environmentally friendly it is, boasting the largest walking bus in the county, with up to 40 pupils using it.

Deputy headteacher, Sharon Walker said: "This is an excellent idea and the children's parents have all been getting involved. It is great to see the children getting exercise before their school day

"Our walking bus has been very popular and we have even won an award for it from Durham County Council."

Esther Brooks, the school's travel plan advisor, said: "We thought a penalty shoot-out would be both a fun and educational way of teaching the pupils about pollution, they have really enjoyed themselves scoring goals against Sam."

Joe Edmonds, ten, from Hamsterley said: "My parents drop me off near school and I walk the rest of the way, I feel more ready for lessons after a good walk. The penalty shoot out has been really fun and I have learned a lot about the environment."

While older pupils were taking part in the penalty shoot-out, the younger children baked cookies in the shape of feet to represent carbon footprints and the importance of walking to school.

National Walk to School Week runs until Friday and encourages parents, pupils and teachers to think about the advantages of walking to school.