Boys will be boys. I’m not sure there’s another phrase that infuriates me quite so much. Since my daughter’s attended school, that’s only cemented the phrase’s place in making me fume.

The first specific moment was during a pre-school open day. Parents could attend the grounds. Outside, boys were zooming along on cars and trikes, directing them at girls and scaring the life out of them. A member of staff looked on, smiling. “Boys will be boys”, she said.

In infant (5–7) school, I became aware for the first time of how girls were used to moderate the behaviour of boys. Classes were broadly evenly split by gender. When possible, a boy and a girl would be paired for tasks. My daughter is now in juniors (8–11) and this continues. The argument for this pairing is boys otherwise misbehave. Throughout, my daughter has complained that most (not all) boys muck around while she’s trying to complete a task. She and other girls are regularly told off for trying to tell boys to be quiet.

At her infant school leaving event, the teachers sweetly said something positive about every child. But it was notable how many adjectives along the lines of ‘funny’ and ‘silly’ were used for boys. For girls, ‘sensible’ was far more common.

And through to yesterday. My daughter came home from school quite upset. During lunch, some boys had decided to throw horse chestnuts at a group of girls. My daughter was hit in the leg repeatedly by their spiny cases, to the degree she was bleeding and this morning has marks that look like a horrible rash down one leg from all the puncture wounds. The initial response from a teacher she told: boys will be boys.

Talking to other parents, all the above isn’t ubiquitous but it’s far from uncommon. And while I’m not an advocate of single-gender education, I can see why it has advocates. As it is, the attitude elsewhere that so often pervades is to our wider detriment. Boys are taught that they can get away with things girls can’t, and push the limits. Girls are scolded when they step out of line and for a moment are not ‘sensible’. And any response to physical harm that’s casually dismissed as ‘boys will be boys’ isn’t setting anyone up for a good future. Society needs to do better.