The Dunblane massacre and the fatal stabbing of London headteacher Philip Lawrence raised school security to the top of the education service's agenda.
But as headteachers were reminded at their annual conference in Harrogate last week, it is parents with grievances - rather than murderous loners or knife-wielding teenagers - who pose the most common threat.
No fewer than 140 members of the National Association of Head Teachers have reported physical assaults or serious threats of violence over the past year. And parents were involved in about 70 per cent of the incidents.
"School security measures can always be broken by parents who come in ostensibly to talk about their children," says David Hart, the NAHT's general secretary. He argues that, despite four years of spending on security, teachers still face too many assaults.
The last violent incident in a school that attracted banner headlines was the machete attack on nursery nurse Lisa Potts in 1997 (the Dunblane and Lawrence murders took place the previous year). But there has been no shortage of attacks on teachers and heads over the past year.
Only three weeks ago, John and Diana Bell were jailed for nine months for terrorising headteacher Sylvia Moore at Francis Coombe School in Watford. Their 12-year-old daughter had been sent home after refusing to remove a nose-ring. In another recent case, a primary head was punched around the head eight times by an angry parent.
Even sport is not immune. A rounders game at a Wolverhampton school last summer resulted in a brawl involving up to 40 people. Teacher Toni Ellis spent two days in hospital after being hit on the head with a bat.
After the Dunblane shootings, the Department for Education and Employment set up a security working party, which reported in May 1996. Its 22 recommendations were largely implemented by the last government, which has made more than pound;20million a year available to schools through the Standards Fund.
In Scotland, Aberdeen has security measures to protect its 80 schools. Alan Baxter, the city's property reorganisation officer, said: "We have had a funding programme in place since 1997. It's been a three-year input of a substantial sum, several millions.
"We have about 8,000 electronic key fobs operated by staff which can be switched on and off centrally. We can set the time and the door that these key fobs can operate and there is even some small use among older pupils. If the fob is lost, it can be deleted instantly from the system."
Cameras are trained on the entrances to every school, and janitors and senior managers are alerted by pagers if doors are opened inappropriately.
Charleston primary school is the first school in the city to be built post-Dunblane. "Security was built into it as a prime consideration," says Baxter. "One of the key things was to minimise the number of entrances and exits and CCTV was designed in.
"When we initially planned these security changes, people argued that perhaps it was an over-reaction to a single incident. Four years down the line people now feel it's a natural adjunct to the running of a school."
In Bradford, school security officer Philip Hoyle has seen a mix of security solutions. "The problems have not all been resolved," he says. "Last year we were given a quarter of a million. We asked schools to bid, but the bids far exceeded the money available."
Bradford decided to offer training to staff and developed a course with Keighley College. Hoyle is critical of some common security solutions, including the ubiquitous visitor badge. "There is no point in giving out a badge if you don't value it," he says. "How many badges does a school have? More than 10? Are they returned?" He believes schools should have a defined number of visitor passes, which should be "chased up" if they aren't returned. "Badges should clearly identify who the visitor is, in letters visible from more than a few inches away."
While recommending that schools should consider CCTV, he also urges people to be aware of its limitations. "Who's watching it, who's going to clean the lens, who's going to watch the tapes?" Roger Mayne is another security specialist who has been consulted by the DFEE. An ex-Scotland Yard detective, Mayne has retired to Cornwall where he is a governor of two schools. "I understand security," he says. "It's what I've done all my life. But you cannot eliminate risk."
Along with most other experts, Mayne argues that security is essentially about access control. "Nobody should be able to have direct access to children or teachers," he says. He is unimpressed by the costly palisade fences many schools have erected. He says that a better option is a combination of physical security with training and increased awareness.
"Schools should plan for the worst-case scenario, and have a simple plan for how an incident will be managed. Who handles the press? Who deals with parents? Involve your neighbours, your staff, the pupils, their parents."
The DFEE says that most schools continue to focus on physical security measures such as CCTV and fencing. Yet the original working party recommended that training should play a key role in school security. The Suzy Lamplugh Trust, which has produced training materials for schools, has also emphasised this.
In Scotland, this has been recognised. Aberdeen offers a one-day course for administration and reception staff, who often have first contact with aggressive visitors. The city has also paid for additional reception staff.
This is not an option for local education authorities south of the border, which can only recommend that schools consider spending delegated funds on security measures. David Hart argues that government needs to consider the wider aspects of security.
The NAHT wants courts empowered to extend parenting orders (under the Crime and Disorder Act 1998) to cover parents guilty of assaults on school staff. LEAs, argues the association, should use injunctions to control individuals. And the Crown Prosecution Service needs to be reminded of existing advice from ministers, that anyone assaulting public servants should be prosecuted whenever possible. David Blunkett has now announced that parenting orders will apply inside as well as outside schools.
"There is a lack of joined-up thinking in government on this issue," claims Hart, who says spending on physical security needs to be matched by an equal determination to deal with offenders and protect teachers.
THE video "Can You See What They See?" from the DFEE is designed to encourage schools to take a fresh look at their security arrangements. It can be ordered free from the DFEE Publications Centre, PO Box 5050, Sherwood Park, Nottingham, NG15 0DL. Tel 0845 6022260. Ref DFEE 00452001.
* DFEE website on school security: http:www.dfee.gov.ukschoolsecurity * Website offering support for teachers and learners, with a section on risk:www.salt.cheshire.org.uk * Books by Roger Mayne on school security issues: "Reducing the Risk"; "Personal Safety"; "Safety of Children". All three pound;25 from Cornwall Centre for Educational Development, 10 Penhaligon Building, Traverson Lane, Redruth TR15 3RG.
Mayne is now developing, through the CCED, a national website with an online security advisory service for all schools, which will include training in risk assessment and management.
* The Suzy Lamplugh Trust is a national charity focusing on personal safety.http:www.suzylamplugh.org
CASE STUDY NO 1. An oasis in a land of sex and sleaze
Derek Hollbird, headteacher of Soho Parish primary in west London, says:
"We're opposite the Paul Raymond Revuebar, just off Leicester Square. Some children who walk less than 200 yards to school have to pass more than 20 sex shops. A lot of male visitors are accosted and the Friday before a big sports event can be very worrying, with big crowds around the school.
"We had some security money three years ago and we now have video cameras on entry. It's been so vital: I don't know how we managed before.
"Last year a number of crack dealers and addicts moved from Charing Cross into Soho. There was a lot of dealing going on, and they were shooting up in doorways. We organised a march on Downing Street. The result was a very high police presence outside the school morning and afternoon. The police wanted to help. The Soho bomb was just 250 yards away, it was just a miracle of timing. Children could have been caught up in it all.
"We were close to the May Day riots. We decided to close on that day. We don't tend to have PTA meetings on site because it's obviously less safe in the evenings, but the school is an oasis in a strange environment: step inside and it's a different world."
CASE STUDY NO 2. Our biggest concern is still strangers
Alan Herbert, acting deputy head of the Ducie High School in Manchester's Moss Side, says: "It's a challenging neighbourhood. There have been drive-by shootings in the area. It is a concern. To ignore it would be wrong.
"The school was extensively remodelled in 1995 and pound;6million was spent - before that the break-in rate was very high. We had a technology workshop with a go-kart and scrambler bikes. Over one weekend they all disappeared.
"One of the first things we built into the new school regime was a security guard after hours and at weekends. But during the day we were still getting strangers on the site. We were a cut-through and there were people drug-dealing on the school grounds. We built an inner perimeter and that helped a great deal. It stops people walking through.
"We then introduced electronic locks on all our main doors. We upgraded our CCTV system and you can now see the perimeter on camera. The CCTV does make it much easier for the security guards at night; over the past three years there has been not one major incident of vandalism or theft.
"We also have security radios carried by staff at risk; the senior management team, PE teachers and staff on playground duty. We offer training on an ad hoc basis to every new member of staff and designated members of the senior staff have had training. New staff are offered a radio, there are telephones in classrooms and the senior management team are on call.
"One of the hardest things to do is to challenge people. You have to try and instil that, but an awful lot of people have access to the site. There is an adult education unit on site, the education action zone is based here, there are mentors, cleaners - even the lollipop man comes in to leave his stick.
"When we installed the security equipment, the immediate reaction from the kids was 'Why are you caging us in?' But there has been a sea change. The Year 7s now say they feel safer. It's not foolproof, but the system does alert us to strangers around the site.
"We know lots of kids who have been injured, or killed, or who are in prison. But the gangland violence hasn't spilled over into school. Our biggest concern is still with strangers."