Come on, Sir, next you'll be telling us the world isn't flat

Science teachers in primary schools are struggling in the classroom because young children are reluctant to give up their own ideas about how the world works.

Science teachers in primary schools are struggling in the classroom because young children are reluctant to give up their own ideas about how the world works.

Research presented today at the British Psychological Society's annual developmental section conference shows that children's false understandings are not easily dispelled by science lessons.

It may be hard to persuade them that, for example, the sun does not turn into the moon at night or that taller people may be younger than shorter people.

Researchers from the University of Hertfordshire, who conducted the study, said that these false beliefs were so hard to change and they could lead children to ignore what they see with their own eyes. Even if a teacher demonstrated an effect with an experiment some children disregarded it, preferring their beliefs.

"This explains why some older students and even adults, still have wrong ideas about some aspects of science," said Dr Karen Pine, co-author of the research. "The challenge for teachers is not to introduce children to new science topics but to help children unlearn their existing ideas."

The researchers interviewed teachers from 81 schools in four education authorities in England.

They said that primary school children had no problem understanding that babies grow into adults or that ice is frozen water. But it was hard to persuade them that heavy and light objects of the same shape fall at the same speed or that large and small objects could weigh the same.

They also found it difficult to accept that a worm is an animal - most children thought that animals had four legs and were furry - or that growth was gradual and continuous. Some children believed they only grew on their birthday.

"If teachers are better informed about false beliefs children may hold it will be easier to use them as the basis upon which to build new, more accurate concepts," said Dr Pine.

But Dr Dorothy Watt, a researcher in primary science education at the Institute of Education, said children's naive beliefs about the world should not be removed completely because they are an intrinsic part of everyday conversation.

"We have a lot of unscientific language built into our everyday conversations such as shutting the window to keep the cold out, when scientifically you shut the window to keep the heat in," she said. "Or that the sun comes up and goes down, when it's the earth that moves.

"There is no point in trying to remove all these ideas from young children, otherwise they will grow up to be dysfunctional human beings. Teachers have to build on them instead."