Hugh Grant has blasted "pathetic" schools and called for a ban on laptops and tablets in the classroom

According to The Telegraph newspaper, Grant described himself as "another angry parent fighting the eternal, exhausting and depressive battle with children who only want to be on a screen".

He went on: "The final straw was when the school started saying, with some smugness, we give every child a Chromebook, and they do a lot of lessons on their Chromebook, and they do all their homework on their Chromebook, and you just thought that is the last f****** thing they need, and the last thing we need."

Dr Haidt, - who is campaigning for phone-free schools - questioned whether the increase in technology in schools was to blame for a decline in test results.

He told the event: "Test scores began going down after 2012. I don't know if it's because of the phones, or because that's when we put iPads and Chromebooks on kids' desks. Whatever it is, as soon as we brought in the EdTech, scores plunged."

Hugh - who has five children ranging in age from six to 15 - said parents feared "rocking the boat".

He explained: "I don't think politicians ever do anything because it's the right thing to do, even if it's the right thing to do to protect children. They'll only do what gets them votes. They only care about their career.

"Therefore, I think the option on this, which is to go after parents, is the right one. Because I think that once you get a critical mass of parents who are outraged by EdTech, as well as all the other issues, the phones, etc, that is when politicians listen because they're scared of that.

"That's also when schools start to listen because they're scared of people leaving their schools and losing business."

He also blasted the "kind of ridiculous posh private schools" he sends his children to for restricting outdoor play, saying: "They're the ones saying they're not going to play outside today because it's raining, or they can't go on the climbing frame because it's windy. It's pathetic. It seems to me that there is space here for a hero school, a set of schools, to break the mould."