That could be either because it is rarely used or because it is successful. Many schools use Circle Time. The idea is that pupils sit in a circle and play games or do something enjoyable for a short time, and then they can discuss matters as a group, including bullying. This is a way for everyone in class to take part in a structured way. This includes listening to the person making the points without making remarks or laughing.
Some schools have a toy or emblem and the only person speaking is the one holding it.
Kevin Sullivan's book gives some very useful advice about using Circle Time effectively, including suggesting that the teacher asks children who know that bullying has taken place in the school to stand up and change places, and then the same question to be asked about bullying in the class. This is a good idea as the teacher then gets an insight into the scale of the problem. I hear an increasing amount from schools and pupils about these strategies which seem to be popular. The idea is that everyone in school knows that bullying is unacceptable, children moving up from primary school are reassured that the secondary school is a safe place to be from Day One. In brief, older pupils undergo intensive training over a number of months into the effects of bullying, and how to care for younger pupils who are unhappy because of it.