DRINK more and you think more, according to children at a York primary school.

Pupils at Lord Deramore's Primary School, in Heslington, are taking part in a project to boost their brainpower using good old Corporation pop.

The theory is that keeping hydrated helps you to concentrate better, and Lord Deramore's is one of a group of York schools testing it out.

Children and staff say it's working and is also making them feel more healthy.

Many of them bring in bottles of water every day, which sit alongside pencil cases and exercise books, and others help themselves from the water fountains installed in school.

Sarah Chadwick, ten, said: "I used to get a lot of headaches, and since I've started drinking water it's just got rid of them. It gives you more energy."

Faye Garland, nine, said: "If you have it on your table it helps you concentrate."

Amy Muckersie, also nine, said she now drank about six glasses of water a day, double the average three glasses she used to (but still below her target of eight).

Head teacher Sheila Powley said the school was one of several York schools taking part in a "thinking skills" project, looking at different ways of helping children to learn more effectively, together with City of York education advisers.

She said: "Research proves that for the brain to work effectively, it has to be constantly hydrated."

Indeed, the theory seems to be in vogue across the country.

At one secondary school in Norfolk, when the fizzy drink machines were replaced by a single machine selling still mineral water, there was much calmer behaviour among students.

Mrs Powley said even the staff were joining in at Heslington, and a new water dispenser had been installed in the staff room.

"It is something that has really, really taken off. I tried it and just drank water for a week and it had a real impact on my concentration."

The school has combined the project with their health education, and another water-drinker, Tom Johnson, ten, was keen to stress the importance of water to the kidneys and of drinking water after sport.

There really was only one down side, identified by ten-year-old David Crawshaw, who proudly brings his England football water bottle into school every day.

"You do have to go to the toilet more times," he said.

Updated: 14:45 Friday, March 01, 2002