Pupils will have their phones locked away in high-tech pouches at one of the city's biggest schools.

Parents will be made to fork out around £25 for magnet-secured Yondr wallets, which they are told will be an expectation from September along with the school uniform at Cardinal Newman Catholic School in Hove.

When students turn up to school at 8.40am, they will put their mobile phone, headphones and any other devices inside the fabric pouch before it is locked at the entrance - making it impossible to access throughout the school day.

Headteacher Claire Jarman said that while the school already has a no-phone policy, too much time is spent enforcing this - and new powers granted by the government allow Newman to prevent children from having access to their phones in the first place.

A letter was sent to parents over the Easter Holiday outlining the school's plans - including the circa £25 cost to use the mandatory pouch, a total of £62,495 if all 2,497 students paid.

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Ms Jarman wrote: "As a school we are increasingly concerned about the impact of smartphones on our young people.

The Argus: The Yondr pouch and magnetThe Yondr pouch and magnet (Image: Yondr)

"Students receive up to three strikes per half term until they are required to hand in their phones to staff.

"Speaking bluntly, this is not working; too many students at Cardinal Newman School are disregarding the rule and failing to hand in when required.

"This is in turn creating a huge workload for our PAMs; time and energy we would prefer to be focusing on supporting students in more positive ways."

The Argus: Principal Claire Jarman in the school's chapelPrincipal Claire Jarman in the school's chapel (Image: Andrew Gardner / The Argus)

She announced a partnership with American firm Yondr which will install the equipment around the school.

This includes magnets at the exits of the school to unlock the devices from the wallets and the pouches themselves.

Our policy will be simple; if you want to bring a smartphone into school, you must have purchased your own Yondr pouch which will then secure your smartphone within, as you enter our school site.

The measures come after a Common Sense Media study found the average young person receives 237 notifications per day - many of which could distract from learning.

A survey by parent-teacher association Parentkind found that 50 per cent of secondary school parents were concerned about the amount of time their children spent on electronic devices.

The Argus: A student walking past the school's front gateA student walking past the school's front gate (Image: Andrew Gardner / The Argus)

The school said the scheme is still in the consultation phase.

"It will be an expectation as part of our uniform policy," Ms Jarman added.

Guidance issued by the Department for Education says headteachers have full government support for banning mobile phones - including at break time.

Lead behaviour advisor to the department Tom Bennett said: "Mobile phones may be ubiquitous, but we have a strong and growing understanding of how damaging they can be for a child’s social and educational development.

"And it’s the least advantaged who suffer most. Many schools already have some kind of policy on phones, but this guidance provides a clear steer for everyone, including parents, about what’s right and what’s not for the wellbeing of the child."