It will be a sensational revelation to the great Scottish public that most pupils in Scottish secondary schools attend regularly, behave reasonably and are generally unarmed.
The notion of knife-wielding hordes ready to strike out at anyone who presumes to mark their sums wrong, while holding obvious appeal for headline writers, is far from the daily experience of teachers. However, doom-laden stories of universal mayhem, and statistics on the rising incidence of assault, do little to reassure ordinary citizens.
One study by a researcher from Nottingham University concluded sagely that indiscipline in schools was really the fault of teachers, rather than the result of any shortcomings on the part of pupils or gaps in their upbringing. This venerable academic may require a new identity and an honorary place in the witness protection scheme to survive the indignant reaction to his conclusions.
We are eruditely informed that his study constitutes "a fundamental attribution shift".
If there is attributing to be done, I would accord credit to teachers across the country for the levels of good behaviour and discipline which they succeed in maintaining day after day, year after year, often in challenging circumstances. They manage to make the curriculum relevant and motivating for their pupils, despite the ever-increasing diversity of backgrounds represented in their classes.
We have all encountered colleagues who could antagonise for Scotland, as well as pupils who hold advanced qualifications in irritation science, but most teachers display admirable levels of patience and forbearance.
We repeatedly tell parents that no one has the right to disrupt a class in Holy Rood. Honouring this pledge requires us to have clear and accessible arrangements which will allow classes to continue when problems occur.
It is essential to prevent situations escalating beyond a level commensurate with the original misdemeanour. Otherwise the miscreant can be given the unmistakable message that he can xert control and have legions of adults in a ferment simply by misbehaving.
Teachers in Holy Rood devised a supervision system which enables situations to be defused and pupils to be accommodated immediately in a location removed from the scene of their crime. The offence may be relatively low-grade, but may be affecting the learning of others.
Individual departments have their own disciplinary procedures and the tone and atmosphere around the school is ordered and business-like.
This session we have employed a young psychology graduate to help us look after some of our more habitual recidivists. Nuala has been recruited and paid as an auxiliary, but she combines the roles of supervisor, counsellor and critical friend. There have been several cases where pupils who otherwise would have had to be excluded have been managed in this way.
External agencies play a prominent role in supporting pupils who struggle to survive within the norms of a mainstream secondary school. Martin Gemmell, our educational psychologist, provides practical, hands-on support to our guidance team in dealing with young people in difficulty. Our education welfare officer, Janice Stewart, brings detailed knowledge of Holy Rood families, with whom she has worked for more than two decades.
There are young people across the country whose needs cannot be catered for within the environment of the mainstream secondary school as things stand. The seriously violent or aggressive minority are impervious to the devices put in place to contain their behaviour. Many of them are dropping off the edge of statutory education at ever earlier ages.
Schools are often helpless in dealing with their problems. Many colleagues consider that there is a general omerta on the entire subject and a national reluctance to tackle the thorny issues they present. Setting national targets for reduction of exclusions may not have them scurrying back to their desks.
Pat Sweeney is headteacher at Holy Rood High School, Edinburgh