Back in the high-and-far-off-times when I first approached the chalkface, there was an unwritten code.
A new teacher is an anomaly; placed in a position of unquestionable authority, in loco parentis, he or she requires obedience and respect from pupils who may be only three or four years younger.
The trade-off for this and for the benefits of the profession - long holidays, a good starting salary and several dozen intelligent and articulate colleagues - was once clear; whatever you chose to do outside the classroom, you never socialised with pupils outside the school setting or allowed them information about your private life. After the heady excesses of your student years, it was time for teaching to claim your soul.
In a small town like the one where I first worked, this had clear implications; most teachers avoided certain places or types of recreation as a matter of course. The consequence of a keen-eyed sixth-former regaling his classmates with accounts of your extra-curricular activities was too much of a risk, however innocent your conduct.
To avoid being mistaken for pupils - a common occupational hazard for recent graduates when academic gowns ceased to be the norm - many young teachers adopted the mannerisms, dress and conduct of their elders while at work. In effect, in many ways, we stepped straight into middle age, as befitted adults expected to set an example of good behaviour to the young people under our literal tutelage.
It was a pact entered into willingly by many who chose the profession - a sacrifice, but also a valuable way to reinforce the pupil-teacher divide as much for our own protection as for that of the pupils. While a few teachers flaunted their grasp of youth culture and their close relationship with pupils, the majority realised that they had to be as far above suspicion as Caesar's wife.
The intervening years, however, have brought temptation in the form of electronic media and thus far greater sacrifices. The same constraints that cause me to hide behind a pseudonym here render it impossible for me to appear online under my own name - and, as for facebook, the case is best summed up in the words of JuliaM (who has written several interesting posts on the subject): 'Facebook and teachers - like matter and anti-matter'.
It's not exactly an overwhelming temptation for grizzled veterans like me, I must admit, but I find something worrying in the way a new generation of teachers seems to have abandoned the idea of sacrificing certain aspects of social life as a result of their choice of profession.
When somewhere between 15% and 30% of teachers claim to have been subject to cyberbullying (depending on your source), you have to ask what they are they doing leaving themselves open to it in the first place. In the same way, one has to wonder about the level of commitment of teachers who allow their drunken holiday snaps to appear in facebook.
Teaching, like monasticism (or, perhaps more pertinently, the Roman Catholic priesthood), once had a dual intake - those with a clear vocation and those who drifted into it for want of something better; the latter were often weeded out within a few years unless they could develop the sense of purpose necessary to cope with the demands of what can be a highly stressful job. It is not unreasonable, I think, to suggest that they would also be more likely than highly committed staff to engage in inappropriate relationships with girls or boys in their care.
Take a closer look now, though, and the waters are somewhat muddier. The DfE is currently advertising bursaries of up to £20,000 for graduates who train as maths teachers - a sore temptation to a debt-laden twenty-something finding today's job market a challenge, even if he or she is temperamentally unsuited and ill-equipped to cope with the unique pressures and demands of a life in secondary education.
The sad truth of the matter is that, even allowing for media exaggeration, a man who tweets pictures of his latest flowery tattoos and expresses himself in overblown song lyrics, with his guitar-playing alter ego and his 'fairytale wedding', 'dream holidays' and romantic gestures, sounds as if he was neither ready nor willing to sign away the trappings of his youthful lifestyle in exchange for a successful career.