Psychologists have been warning us about this for years: the mental health problems it causes, the loneliness, the breakdown in family communication, the inability to concentrate for more than 20 seconds. But our concentration spans aren’t long enough any more to pay attention to the warning bells.

My friend with a two-year-old son doesn’t imagine for a moment the future problems she is handing to her little boy as she sits down to lunch with me and gives him her phone to occupy him. She doesn’t see into the future when he is 12 and she will be desperately trying to get him to put the phone down in order to pick up a book instead.

Not all aspects of the new technology are bad, of course. In order to reach all of our school parents, we made a video of me talking to the camera, giving advice about the evils of technology, and then we sent it to them via text. Why? Because we knew that they would all get it. No one is ever far from their phone. School letters, on the other hand, often end up at the bottom of a child’s bag.

We also set a lot of online homework. Pupils have the choice to stay after school in the computer room to complete the homework. It saves the teachers many hours of marking time and gives the child instant feedback. If they are doing it at home, there are videos teaching them what they might have forgotten from their lesson. The internet has helped us to transform homework in useful ways. But if homework is in constant competition with more “fun” stuff on the internet, then it will never be done properly.

Dealing with addiction is hard. It is especially hard when the world doesn’t even recognise the addiction.  The most maddening thing is that while the children are meant to be working they are having interminable group chats on WhatsApp complaining about how they have too much work to do. The reason they do this is because they are continually counting how many views, likes or subscribers they have. Make a rap with racist, misogynistic language — as some children as young as 13 are doing — and your popularity soars. It is hard to resist online fame.

The most worrying thing is the damage these networks do to their abilities. Children no longer watch television. Even if a child has not had access to books at home, other things such as films, soap operas or TV dramas would expose them to a narrative. But a story with a beginning, middle and end is a thing of the past these days. Snapchat and Instagram provide 10-second recordings where you follow someone as they film themselves with their smartphone, walking down the street — “Just on my way back from the hairdressers.” No moral at the end of the story and no attention span required to follow it.

For the first time in history, parents cannot filter what their children see or who they communicate with. Parents say that they want their child to have a phone as a means of protection, something they can track their whereabouts with. But this is a two-edged sword. If your child uses a flash smartphone in public they are an easy target for crime. They are also meeting all kinds of undesirable people on the phone. Once upon a time, the older kid who was a bad influence would have had to physically meet one’s child to lead them astray. Now it is done in the middle of the night via Snapchat without the parents’ knowledge.