For anyone familiar with teenage love, the following tweets would seem less than extraordinary.

“I am with the most beautiful amp; amazing person in the whole entire world who I love with all my heart . lovely girl you’re the beauty in my world.”

“Hello baby, you are perfect,” she replies. “I just want to run away for ever.”

But just weeks after this somewhat anodyne exchange, the couple provoked a national furore when they did flee together, to France. For while the language of the tweets might have suggested a typical first romance, this was a highly inappropriate relationship between a 30-year-old maths teacher, Jeremy Forrest, and his 15-year-old pupil, Megan Stammers.

Furious parents at Bishop Bell C of E school in Eastbourne, Sussex, where Forrest had taught, demanded a wider inquiry after it was revealed that the couple appeared to have been in a relationship for up to seven months.

Not long after, it emerged that another teacher at the school had been jailed three years ago for grooming and sleeping with two girls aged 15 and 16, while the former chairman of governors was due to stand trial on child sex charges.

Public, parents and education authorities were unanimous in their condemnation and a rash of newspaper articles followed about teachers who had seduced their students - usually featuring interviews with anonymous pupils, most of whom said in retrospect that they felt betrayed.

“He ruined me, sexually, emotionally and in every other way possible,” said Sophie (not her real name), who was 17 when her 25-year-old teacher seduced her in 1992. The full horror of it hit her afresh, she said, when she read reports about Forrest and Megan. “I was naive and innocent, and he was perverse,” she added in an interview with a national newspaper. “The sex was aggressive and sickening, but I was infatuated; he was this older man. All the girls fancied him. I’ll be honest: we were all after him.”

If the voices of teachers were largely absent from this public debate, behind the scenes, in online chatrooms, dozens were busily fuming, condemning Forrest and the impact his actions were likely to have on their already beleaguered profession. “Everyone knows the rules,” was the underlying sentiment. “This man is an idiot” was another more blunt, and commonly expressed, view.

The affair between Forrest and Megan faded from the spotlight only after being overwhelmed by the scandal around Jimmy Savile, where we learned that a man regarded as a “national institution” had been allowed to prey on underage girls throughout his decades as a celebrity. Back in the classroom, the rules for teachers about relationships with their pupils are clear. Under the Sexual Offences Act 2003, it is a criminal offence for a person over the age of 18 who is in a position of trust over anyone under that age to involve the younger person in any form of sexual activity. The offence first appeared in the Sexual Offences (Amendments) Act 2000 and covers, among other organisations, institutions looking after young people, hospitals, care homes, children’s homes and educational institutions. Before this, it had not been illegal for a teacher and a student over the age of consent to have an affair, although most schools had their own, much stricter, protocols. In the past, a few might even have sometimes turned a blind eye. But they always took a dim view.

The NUT and the NASUWT teaching unions insist that pupil-teacher affairs are “very rare”. The NASUWT, which chose not to contribute to this article - “we have been asked a lot about this issue (since Forrest and Megan) and we don’t want to comment” - has previously said that it dealt with about 800 allegations of misconduct against its members each year but that only five or six involved inappropriate sexual contact (most concern alleged physical abuse).

Yet in 2007, a YouGov survey of 2,200 adults said that one in six people knew of someone who had had an “intimate relationship” with a teacher while at school. And a former deputy headteacher, who wants to remain anonymous, explained to TES recently: “It happens a lot more than people think. But nobody wants to talk about it.”

So where does a teacher turn, if they notice that a colleague appears to be crossing the professional line in the bond they have formed with a student? Or worse, what do you do if you are the teacher who is developing inappropriate feelings for a student?

Julian Stanley, chief executive of the Teacher Support Network, says that all schools should have a safeguarding policy in place so that teachers can report a concern about the conduct of a colleague. But he emphasises that the purpose and nature of the role of the teacher should be impressed upon trainees by the training institutions.

“We would always advise teachers not to get involved with pupils on a personal level, to protect both the pupils and the teachers from the consequences,” he said.

“If a teacher called our support line with these issues, we would offer support for any distress they were in. However, if we heard they were a danger to themselves or others, as a matter of policy we would break confidentiality and contact the relevant authorities.”

The danger of social media

The rise of text messaging and social networking sites such as Facebook and Twitter has brought a new raft of potential problems. Teachers who use these sites could risk becoming more personally involved with their students than is healthy, or their comments could be misinterpreted to appear that they have had - or are having - an illicit relationship with a pupil.

More than one in 10 teachers accused of misconduct last year had used social networking sites and email to forge inappropriate relationships with their pupils, according to an analysis of figures from the General Teaching Council for England (GTC). Facebook, Twitter, online chatrooms and emails were used to befriend children in 43 of the cases brought to the GTC. Eighteen teachers were given prohibition orders and struck off, and 14 were suspended. The GTC heard 336 cases of “unacceptable professional conduct” last year. But there remain big differences between schools’ policies on social networking: some ban teachers from having accounts entirely, whereas at others staff can be Facebook “friends” with their pupils.

The unions are concerned enough to offer “e-safety guidance” and workshops for teachers to help them stay on the right side of the law.

“Technology has allowed for some blurring of the traditional boundaries between private and public spaces,” says Amanda Brown, the NUT’s assistant secretary for employment conditions and rights.

“People have not always thought about this, but the same sort of criteria should be applied to social media as you would apply to usual face-to-face relationships.

“Teachers must make sure there is a dividing line between their professional life and private life. For example, don’t give out your personal mobile number, take personal calls from pupils or use personal emails to deal with pupils. It is easy to misinterpret emails or texts.

“Technology is moving on all the time. It is sensible to lay down guidelines on how teachers should behave and use these technologies with pupils. It can be a problem because pupils have bullied teachers through social media. We have set out an e-safety policy that reminds members how to work safely.”

If teachers are concerned that a colleague might have crossed a boundary with a pupil, there should be someone within the school who they can talk to.

“Generally any teacher who has concerns should report them to a colleague within the school who has been given the designated responsibility; there should be one in every school,” says Brown. “This takes the personal difficulty out of it.

“It’s important to make colleagues who may have noticed something feel that they are not being a snitch. This is a child protection issue. There should be policy and procedure and everyone in that school should know how to report this. If you follow that procedure you don’t have personal dilemmas.”

There is, perhaps, a lingering, if unspoken, double standard that while a teenage female student is “preyed upon” by a male teacher, a teenage boy who has a sexual experience with an adult female teacher “has had all his dreams come true”.

One man, who wrote to TES anonymously about a cycle of abuse he endured years ago at school, appeared to confirm the cliche. He said: “I joined a comprehensive in my home town at the beginning of Year 9 and within a month was sleeping with my English teacher . I have been encouraged by my therapist to view this second episode as equally abusive (he had earlier been abused by a male housemaster), though I have found this difficult to do.”

For teachers who have such a relationship, however, there is no such ambiguity: this is the stuff of nightmares and will almost certainly result in their losing their reputation and their livelihood. (One male newly qualified teacher was so terrified of potential relationships and misunderstandings with female students that he told a friend on graduation: “I’m only applying for jobs in all-boys’ schools.”)

But it is also deluded to think that students cannot be predatory. Ten years ago I interviewed Katherine Baillie after she reappeared with her former maths teacher boyfriend Paul Tramontini after being on the run for 415 days. She was 14 and he was 32 when their relationship began. He was sentenced to 18 months’ prison for abduction, although he served only half the sentence. Baillie revealed to me that she had stalked Tramontini, despite his repeated resistance, even visiting him at his home with a love letter, she had been so desperate to start the romance. “He saved me,” she insisted, when talking of her then dysfunctional relationship with her own family.

Baillie was a troubled teenager and it was easy to see how Tramontini must have been concerned about her. She had told him that she would run away on her own if he did not go with her. And she was so jealous at the time of my interview that when she was told that Tramontini had been visited by a female officer in prison, she burst into a fit of violent rage and smashed up the hotel room where the interview took place. When Tramontini was released, they wed, although seven years later they divorced and Baillie is now married to someone else. As an adult, she now sees their relationship very differently. Needless to say, Tramontini is no longer a teacher.

Only a few years ago, Chris Keates, general secretary of the NASUWT, sparked outrage when she said during an interview with the Tonight programme that teachers should not face jail for having sex with pupils who were over the age of consent. Critics of the current law point out that there are plenty of examples of other young or even older men who forge romances with school-aged women over the age of consent.

One TES reader, Philip Hodson (not the sex therapist of the same name), went even further, arguing that it is normal for 15-year-old girls to “die” in their desire to have sex with their teachers - “preferably the married ones”.

“In the 1960s and 1970s, these events were gently tolerated and put down to `learning to grow up’ and they usually peter out anyway,” he wrote, shortly after the affair between Forrest and Megan came to light.

“Today we hear the word `sex’ and our hackles rise. We hardly know that a loving matter can be occurring. We think only of abuse. For every heterosexual relationship, if there is a whiff of age difference or underage activity this is a heinous crime to sex-abuse authorities, and anyone who may dare to question the stance of the authorities is a sex criminal too.”

It was a view commonly held in some quarters in the 1970s, when the era of “free love” suggested that young teenagers should be allowed to “enjoy” sex with older partners. A minority even lobbied to lower the age of consent.

Today’s climate is wildly different, and those in charge of protecting children would say that Hodson and others are missing the point. For however sexually aware and strong-minded teenagers may be, they are still easily influenced by people in positions of power - and they are vulnerable. Now such an unbalanced relationship is regarded as abuse.

`Treat it as a problem, because it is’

But TES behaviour expert and author Tom Bennett is not surprised that school affairs still occur. He says it is “ridiculous” to assume that no attractions ever exist between students and teachers.

He adds: “For the teacher, the simplest mechanism is to remember his or her role: a teacher, a guardian, a mentor. Not a friend. If a student hangs around too much after lessons, if they seem too happy to unburden themselves of their every personal moment, then they are starting to see you not as an authority but as an intimate. And that rarely ends well. Never get too close, because it hinders your relationship with them.

“The first thing I was told in an all-girls’ school was to always keep a door open. If you know someone is making baby-eyes at you, don’t be wet and feel flattered. Treat it as a problem, because believe me it is.”

Bennett has little sympathy for teachers who cross the line. “The teacher who forms an actual relationship with a student is demonstrating enormous levels of selfishness, and rightly enjoys public pillorying. They have put their own emotional and physical needs before the needs of the child. They have abused the trust that society and the child have bestowed.”

Jenni Whitehead, a former editor of Protecting Children Update, a newsletter published 10 times a year, agrees. She says that one of the more troubling aspects of the view that Keates expressed is that it could be interpreted to mean that children held some responsibility for the corruption of teachers.

She cites a newspaper article based on an interview with a young man who at 15 had been seduced by his dance teacher, who was quoted as saying the affair had “ruined his life”. One response, posted after the article appeared, was not an uncommon view: “When I was 15, none of the lads in my class would have turned her down. Ruined his life! Oh yeah.”

Whitehead says: “Managing a young person’s crush can be extremely difficult. Staff can feel isolated and vulnerable and may make matters worse by trying to manage the situation on their own. Make sure that this issue is dealt with as part of the induction process and try to create an ethos that would make it easier for a member of staff to ask for help where they are the subject of someone’s crush.”

It seems that both teachers and young people need protecting from inappropriate affairs, which can ruin young lives and end promising teaching careers.

Staying safe

• Do not share your personal phone number with students.
• Do not reveal details of your personal life.
• Keep your Facebook page personal and secure.
• If teaching only one pupil keep the door open and where possible a window open. Do not sit close to the pupil.
• Avoid any unnecessary physical contact with pupils.
• Try to avoid engaging with students outside school, personally or electronically.
• If you are concerned that a student is becoming too attached to you, report the situation to a senior member of staff and seek advice from your union.

• Reporting concerns

Any teacher who has concerns about a colleague crossing the line in their relationship with a student should report them to the designated child protection teacher within the school.

Every school should have a child protection policy and all staff should have received training in the procedure to be followed.

It is important that colleagues understand that concerns will be acted upon.

The protocol should be kept up to date. Problems can also arise where basic measures have not been taken, or when not every teacher is aware of them. These should be in place before any situation develops.

Photo: Megan Stammers ran away to France with her maths teacher Jeremy Forrest, causing a media storm. Credit: AlamyRex montage