Spitting, swearing and fighting in the playground? All in a day's work if it is the pupils doing it. But what if it is the parents who are thumping each other? It happens. Not content with rolling up to school to lambast teachers for picking on their children, parents are more than capable of picking on each other in the playground.
Peter Fowler, head of Granby primary in Leicester, has seen it for himself.
"Parents have fought in the playground, sworn and shouted abuse at each other," he says. "One lay in wait for another to attack them. It has got to the point where I have excluded more parents from the site than children."
Most teachers can tell tales of irate parents bursting into lessons, determined to let rip at the teacher who has given detention to their little angel, or failed to sort out a squabble between classmates. And heads are wearily familiar with the torrent of abuse which can ensue if they call in parents to discuss a pupil's challenging behaviour. Not only is it a nationwide problem but it is not confined to schools. Staff in any job which involves dealing with the public, be it a nurse or paramedic, railway worker or in a benefits office, are facing increasing threats of violence.
But what can you do about it? The most successful schools appear to have a two-pronged approach: prevent problems by building good relationships, and repel unwelcome visitors with good security. Flashpoints are rarely teaching and learning but misunderstandings, anxiety, family tensions, and often parents' own memories of bad classroom experiences.
Moyra Healy, an independent behaviour consultant, who has advised schools and the Government, believes treating parents properly is the way to break the cycle of poor parenting which can provide the seeds for abusive confrontations at school.
"A lot of schools send for parents when a child is in trouble," she says.
"They say, 'Would you wait outside the head's office?' They are treated like they are 15, and start reacting as if they are. We have to change that. We have to show we are supporting them both, not judging them as parents. The message should be, 'There is no criticism of anyone here but your child has a need - everybody has needs - maybe an issue with anger or how to behave in the classroom. We need to work with your child so she can be the best child she can be, for herself'."
David Brandon-Bravo, head at Parkfields middle school in Dunstable, Bedfordshire, agrees. "The pre-emptive strike is absolutely fundamental. If you identify a child as potentially having a problem, get good news home as much as possible, and build up a relationship with parents before it becomes an issue."
And you have to be prepared for schools to get caught in family crossfire and know how to deal with it, he says. One of his pupils found that complaining that the school was institutionally racist got more of her father's time. So the father decided to pay him an angry call. "I suggested he change his working hours and not react that way to the child's behaviour. The father was angry but he did those two things and her behaviour improved dramatically."
One solution could be the new pilots for parent support workers, recommended in the report on behaviour in schools chaired last year by Sir Alan Steer, head of Seven Kings high in Ilford, Essex.
Sir Alan says: "We want somebody to invest in providing skills and resources to deal with the small number of vulnerable parents. You do get parents from hell, but not many, and quite often you can unpick these issues with time and effort. If you want respect you've got to give it.
Treat people respectfully, speak politely to children, have clean surroundings, and a trained receptionist to treat people properly. We're not strong on training. How much training do receptionists and caretakers get? And yet these people, more than teachers, often have to handle difficult situations."
Inexperience can put new teachers at a double disadvantage. James Williams, postgraduate certificate in education lecturer at Sussex university, says many trainees need reminding that not all adults are like their own parents.
"We say to them, if you've got a very angry and upset parent, calm them down. Be polite. Establish a relationship and, if there's a problem, put your side of the argument.
"But don't come across as an authoritarian. The younger you are, the more important that is. The person may be in their 40s with a son of 12 or 13 - you don't want to appear patronising."
The final resort is banning parents. Peter Fowler at Granby has excluded three or four children in 11 years, and 11 parents. "You don't want people on school grounds using inappropriate behaviour, you want them to set an example," he says
If the worst happens...
Do try to offer the person a way out. Suggest going for a walk or finding a colleague to mediate. If necessary, allow the person to divert their aggression to inanimate objects such as hitting a table.
Do respond slowly, calmly and gently. Breathe slowly to control your tension or anxiety.
Do report the event and ensure the investigative process is fair to you.
Don't respond in kind as this may worsen the situation.
Don't come across as intimidating. Threatening gestures can include looking down on the person, folding your arms, having your hands on your hips or raising your arms. If you can't contain the situation, get away. Ensure you have access to the exit.
Source: Teacher Support Network
For more information and help Association of Teachers and Lecturers: advice, including a model school policy on abusive behaviour, can be downloaded free via www.atl.org.uk. For a hard copy call 0845 450 0009, product code PE28 - free to ATL members or pound;9.99. Toolkit of advice from the DfES
www.teachernet.gov.ukwholeschoolbehaviourSteer report: www.dfes.gov.ukbehaviourandattendanceaboutlearning_behaviour.cfm