A new law banning mobile phone use in schools in England, which ministers reluctantly agreed to last week, is on one level the result of political manoeuvring by Liberal Democrat and Conservative peers – who forced their hand by threatening to derail the schools bill. Until now, the government’s position has been that advice to headteachers was sufficient. But whether or not a ban turns out to be helpful, the campaign reflects deepening public concern about the degree to which powerful tech companies can be trusted.

From messaging platforms where pupils and teachers interact, to appointment-booking systems and research carried out in lessons and at home, digital technology is deeply embedded in education. This should not be expected to change. Classrooms rightly reflect the wider world that they are part of. But the current push towards stronger scrutiny of screens in schools – and in young people’s lives more broadly – is justified by accruing evidence about their impacts.

In Norway and Sweden, policies promoting the use of iPads and laptops have been reversed in favour of books and handwriting after both countries recorded drops in reading scores. In the UK, new guidance recommends that under-fives should spend no more than one hour on screens each day, and should not watch fast-paced, social-media style videos at all. Even in California, home of the US tech industry, the mood is shifting: from September, elementary (primary) and middle-school students in Los Angeles will face restrictions on device use.

Whether legal age limits, advice, or a focus on what happens in classrooms is the best response is highly contested. While some regard Australia’s ban on social media use by under-16s as the start of a global pushback against an over-mighty industry, others are ready to dismiss the policy as a failure four months after it was introduced.

Clearly not all tech is the same. But the point being made with growing confidence by researchers is that not all brains are the same either. Children and adolescents have specific needs and vulnerabilities and are at risk of being harmed when these are targeted by businesses. Whistleblowers including Frances Haugen have highlighted teenagers’ susceptibility to the preoccupations with status and appearance that are used to maximise engagement. Early-years experts such as Prof Sam Wass are convinced that the brain and language development of the youngest children is hindered by hyper-stimulating, attention-grabbing content.

From George Eliot to Martha Nussbaum, there is a long tradition in the humanities of belief in reading as socially beneficial, because of the curiosity and sympathy for others that it engenders – and this is another source of concern about the impact of replacing books with devices and their personalised, algorithmic feeds.

Adults are not immune to these changes. All people exist in a dynamic relationship with the tools that we use to communicate. The dilemma is that while public policy is meant to be evidence-based, the researchers who analyse technology’s impact cannot keep up with the pace of development.

Up to now, the approach to big tech has generally been laissez-faire. One would need evidence from a counterfactual reality to state with confidence that this has been a mistake. But the case for a more precautionary style of regulation is at last being taken seriously where it arguably matters most – in relation to the growing and impressionable minds of children.

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