Schools told to go phone-free all day as Government targets pupils’ social media use

Bridget Phillipson said it was "not appropriate for phones to be used as calculators, or for research" both inside and outside of class time.

Last week, the government issued updated guidance around phone use in schools, stressing pupils "should not have access to their devices during lessons, break times, lunch times, or between lessons".

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The Department for Science, Innovation and Technology (DSIT) said it will also be taking immediate action on children's social media use, including directing Ofsted to examine schools' mobile phone policies and how effectively they are implemented during inspections.

"Schools should make sure those policies are applied consistently across classes and at all times and we want parents to back these policies too," Ms Phillipson said in her letter.

Teachers have also been advised not to use their phones in front of pupils.

According to data supplied by the DSIT, 99.9 per cent of primary schools and 90% of secondary schools have mobile phone policies in place.

However, 58 per cent of secondary school pupils reported mobile phones being used without permission in at least some lessons, rising to 65 per cent for key stage four pupils.

Paul Whiteman, general secretary of the National Association of Head Teachers, said school leaders "need support from government, not the threat of heavy-handed inspection".

The Government should support schools to help them store pupils' mobile phones during the day, a union has said, after the education secretary wrote to head teachers to stress phones should not be used at school.

The Association of School and College Leaders (ASCL) welcomed the letter, but said the challenge for schools is the practicalities of enforcing phone bans.

ASCL general secretary Pepe Di'Iasio said: "We would therefore like to see Government support in providing schools with the resources needed for the safe and secure storage of mobile phones during the school day, ensuring that pupils cannot access these devices at all."

Ministers have launched a consultation on implementing an Australian-style social media ban for under-16s in the UK.

The consultation will look at options including raising the digital age of consent and restricting potentially addictive app design features such as "streaks" and "infinite scrolling".

Ministers will visit Australia as part of the consultation, where a social media ban for under-16s came into force in December.

The Government will seek views from parents and young people and will respond in the summer, DSIT said.