Almost one million school children spend most lessons learning from screens despite evidence that too much exposure may be harmful, according to polling.

New research suggests nine per cent of all pupils in the UK – around 960,000 – spend nearly every lesson on a 'one-to-one screen', such as an iPad or other tablet.

Among primary school children only, the proportion is six per cent – around 270,000.

Popular apps in schools include Minecraft Education, which is based on the famous computer game, and language tool Duolingo.

A further quarter of the entire pupil population – or 2.6 million – are using screens on a daily basis.

The polling is by campaign group SafeScreens, which is calling for all one-to-one screens to be banned from classrooms.

On Sunday, Laura Trott, Shadow Education Secretary, said: 'We have drifted into a major experiment on our children.

'Nearly a million pupils are spending most of the school day on screens despite little evidence that it improves learning.

'Having finally recognised the harms of phones and social media, Labour should be helping parents reduce children's screen time.'

The poll, involving a nationally representative sample of 2,000 parents, was carried out by Focaldata for SafeScreens.

It also found 26 per cent of parents said that using screens for learning has made it harder for their child to concentrate in lessons.

In addition, 28 per cent of parents said that technology use had caused safeguarding issues at their child's school.

Jane Rowland, of SafeScreens, said: 'We have sleepwalked into a giant experiment being conducted on a generation of children, and nobody consented to it.

'Primary schools should be device-free by default, full stop. In secondary schools, pupils' use of one-to-one devices, apps and AI tools should be suspended until robust, independent evidence can confirm that they are safe, privacy secure, and educationally better than a non-screen equivalent.

'And even then, every parent should have a statutory right to opt their child out.'

It comes after the Government announced plans for artificial intelligence (AI) tutoring tools to help disadvantaged children catch up.

However, the Education Select Committee is currently conducting an inquiry into the use of AI in education, saying there are 'risks' in deploying it 'without a full understanding of the consequences'.

The Government plans to publish guidance in the autumn on screen use for children aged five to 16.

It is also banning smartphone usage in schools and outlawing some social media platforms for under-16s.

Screentime has been linked to shortsightedness, and eye doctors have warned this may be the cause of the global rise in children needing glasses.

In addition, studies have found that children's attention and memory can be impacted by excessive playing of computer games – which many education apps feature.

A Department for Education spokesman said: 'Personal and educational screen time are not the same thing – what matters is what children are using their screens for.

'Used well, technology is a powerful tool to support learning and free up teachers to deliver the excellent education every child deserves.

'We're taking action to make sure children use screens safely from the very start. We've published early-years screen time guidance, are developing the first-ever guidance for 5-16 year olds, are supporting the building of safe AI tutoring tools, and are banning the social media we know has harmed the development and mental health of under-16s.'