In the early days of my teaching life, I taught science in a comprehensive. One of the main foundations of our behaviour policy was a warning system: if a child reached a certain number of warnings, they were collected by whoever was on duty, and isolated.

I remember at the time thinking that it was helpful to me as a teacher, but I now realise that its fundamental weakness was that it simply expedited the end of lessons for children who found school a difficult place to be.

My biggest mistake was issuing warnings publicly so the rest of the class could hear, in an effort to set an example to others. In a similar vein, I noted warnings on the board next to children’s names. Looking back, I was unnecessarily escalating situations by shaming children.

In the early days, I could have quite a few names on the board with tally marks against them to keep track; this was a crystal-clear indicator to any visitor that I had lost control of my lesson. (I could walk into a lab after someone else’s lesson and see tens of warnings on the whiteboard - those were lessons on life support.)

I’d unwisely decided that the public display would communicate to the children the seriousness of what was happening. Unfortunately, it had the opposite effect. Some of the children amassing warnings found it amusing; others responded aggressively.

Writing children’s names on the board, class traffic-light systems (which seem to be endemic), or standing children at the front of assembly may be regarded as deterrents, but they are counterproductive. A child can try to cope with, or defend against, public shaming in one of four ways:

• Withdrawal: you may see behaviour such as introversion (hood up, head on desk, refusing to speak), or they might walk out or avoid a lesson.
• Attacking self: contempt or anger is directed inwards and can be magnified. You might see a child ripping up their work in response.
• Attacking others: anger is directed outwards, and not necessarily toward the source of the shaming. You may see behaviours such as damage to property or attacks on other students.
• Avoidance: a form of denial. For example, I have seen children lined up on stage behind the headteacher for being improperly dressed, aping his actions during the assembly.

Any recourse in a situation that requires us to appear tough can lead to public shaming, but it’s unnecessary escalation and should be avoided.

Jarlath O’Brien works in special education in London. His latest book, Better Behaviour: A Guide for Teachers, will be published by SAGE in June. He tweets @JarlathOBrien