Education is about teaching the truth, while advertising is the art of warping it in favour of the seller. Teachers are obliged to tell children the facts as they see them, while advertisers conceal the ones that might inhibit sales. It is not quite as clear-cut as that, but there is often some degree of incompatibility when the two alien kingdoms are forced together.

Headteachers composing job advertisements briefly turn into estate agents. The odd scarred tree, much beloved by local dogs, becomes a wooded haven. The school is teeming with modern technology (one magic lantern and two rulers).

Applicants are invited to fit into a happy and contented staffroom where never a cross word is heard, to the undisguised glee of its occupants, who regularly break the British all-comers’ 100-metre record down the corridor whenever the deputy head enters looking for someone to cover for an absent teacher.

It was not surprising to read that some private schools have been rapped by the Advertising Standards Authority for exaggerated claims. Put people in a competitive situation and some will overrate their virtues. Politicians do exactly the same. Spin doctoring is just advertising without the jingles, though it cannot be long before someone writes a tune for “I am bloody wonderful, vote for me.”

Now Iain Duncan Smith has started to launch his education campaign as champion of the vulnerable. You have to laugh at the barefaced cheek of it. Could these be the same children whose schools were left to rot during the many years when his party refused to spend money maintaining or equipping them to a decent standard? Leaking roofs and peeling paint were a national disgrace. At least the Conservatives now have a competent education spokesman in Damian Green, though I hesitate to ruin a promising career by saying so.

Dunkers asserts that children in Conservative-controlled areas do better academically than those in inner cities, often Labour authorities, as if the reason is entirely down to the influence of politicians, and poverty and disadvantage play no part. This is pathetic even by the low standards of spinning in political circles nowadays. Advertising the teaching profession has been developed to a fine art by the hapless Teacher Training Agency. Its “No one forgets a good teacher” campaign cost pound;10 million - but fewer applicants signed up. Bribes such as golden hellos have now produced more recruits, but TTA adverts omit to mention those leaden goodbyes when large numbers leave the profession within three years.

Indeed, the symbolism of the present generation of TTA adverts has been completely misinterpreted. Analysts claim that the film images all portray positive aspects of teaching. I beg to disagree. The opening Halifax ad-style aerial shot of people is not “someone to look up to”, but rather teachers waiting for the next load of fertiliser to land on them. The woman and the maze are supposed to illustrate the challenge “Could you find a way in?”, but they really mean that recruits will soon be lost in a jungle of paperwork.

Similarly, the face with moving lips has nothing to do with teaching a language. It is actually one of the 45 per cent of teachers who quit teaching within three years mouthing the words “Do you have any vacancies in your tripe factory? I’m out of here.” The clouds scudding across the sky are not indicative of the infinite possibilities in education, but are symbolic of the uneasy feeling that teachers are about to be peed on by yet more daft initiatives.

We need ads that make a virtue of being brutally honest, like the one for Marmite which admits that some people actually hate the product. The text writes itself.

Scene one: “Hello. We’re the Teacher Training Agency and we’re clueless.”

(Shot of man trying to put glove on head).

Scene two: “But we do have lots of money (picture of big bag marked “Swag” with banknotes falling out of holes), so we’ll give you some if you promise not to drop out of teaching in - ooh - less than three weeks.” (Happy ex-teacher shown lying on beach lighting cigar with pound;50 note plucked from bag marked “TTA golden hello”).

Scene three: “If you want a job where you can use your initiative (shot of teacher with head locked in large vice labelled “Government-prescribed geography hour”); where you will be paid according to your experience and expertise (montage of young, fast-tracked physics teacher in new Jaguar coupe while elderly music teacher is being offered a bunch of carrots); just say yes, yes, yes to the DFES.” (Closing shot of jolly person putting on jacket back to front).