The government has stars in its eyes – and it is proving confusing. It has introduced a new A* grade at A-level to help universities distinguish between top candidates. Then, last week, it instructed those same universities to ignore the new grade “for several years”.

What has brought about this abrupt change? The government says it fears teachers will find A*, a pass rate of 90% or above, hard to predict. That might be true over the first year but over several years?

Universities fear the real reason is more to do with politics than education. Education, like health and the police, is subject to political pressure in order to make the government look good. External exams are high-stake tests as much for ministers as pupils. The government worries that privately educated pupils will dominate the grade. It will show up once again the chasm between private and state education.

The government’s efforts at manipulation are nothing new. In a tight educational spot, it huffs and puffs at universities rather than address the real problem – the politicisation of education. At every stage of our state system, political considerations override pupils’ interests. The damage this has caused is incalculable I have spent the past nine months interviewing youngsters who are now on the streets or in and out of prison because no one taught them to read and write between the crucial ages of five and seven. And no one, in seven subsequent years of education (most dropped out of school at around 14) addressed the problem. One young man explained: “For my first two years of secondary school, I was in the top sets for maths and science, but rubbish at everything else because of my lack of literacy. That kills you in every subject. Even in maths you need to read the question.” The government’s “literacy hour”, he says, is not working. Instead of being at university where he belongs and where, as a potential science graduate, the economy needs him, this bright and articulate 22-year-old lives on benefits in Hastings.

In the office of one headmaster, a series of elaborately coloured graphs covered the whole of one wall. He had put them up for a reason. They proved to visitors from government departments why some of his students had failed to make the expected progress. Despite impressive Sats at age 11, they had arrived from primary school taught to do the test but not much else. He lacked the staff or funds to help them catch up.

Instead he was concentrating on working a similar conjuring trick, “ducking and diving” as he put it, between exam boards in order to increase C grades at GSCE. The head was gleeful that morning. He had discovered an English GSCE that did not require his pupils to read a single poem or book. “You have to be ahead of the game,” he said.

He is not alone. One teacher on an educational forum admitted he switched all his economics candidates from one exam board to another and doubled the number of grade As. “How,” he asked, “do you think the ‘tough’ exam board reacted to its customers going elsewhere?” He went on bitterly: “We have a smoke-and-mirrors system which suits the politicians nicely. Teachers have no choice but to play the game.”

Unfortunately, this game affects the lives of disadvantaged children. Last month Jim Knight, the schools minister, hailed the success of schools reaching a government target one year early – 60% of 15-year-olds gaining five higher level GCSEs (worthless in itself because it does not include maths and English). But what price have young people paid for Knight’s moment of glory?

John Dunford, general secretary of the Association of School and College Leaders, is clear. The league tables have created perverse incentives. Schools are forced to skew the curriculum for 14 and 15-year-olds towards subjects “in which it is easier to reach grade C”. A-levels create similar perversions. This might benefit schools and Knight, but it has severe consequences for teenagers, especially from a poor background.

To be sure of meeting government targets, schools are deliberately pushing even able pupils away from difficult subjects such as science and languages. But these traditional subjects are the ones the universities want.

“Soft” subjects, anything with a “studies” in it, as one headmaster remarked, do not win places at a good university. Geoff Parks, director of admissions at Cambridge, said: “We know the schools’ bright students are on track to get As, but in subject combinations that essentially rule them out.”

This has devastating consequences for disadvantaged teenagers. They are the most reliant on their schools for correct advice on universities and careers. They must trust that their schools have their best interests at heart. Too often this is not the case, as the Sutton Trust has discovered. An online questionnaire of 3,000 students revealed half believed there was no difference in earnings between graduates of different universities.

Schools had also failed to warn them of the importance of their choice of subject. They had no idea it would dictate not only which university would take them but also their future salary. According to London University’s Institute of Education, a decade after leaving university, a fifth of graduates from leading universities earn more than £90,000 a year, compared with just 5% of those from the so-called new universities.

The state school pupil who manages to get to university faces yet another piece of government hocuspocus. More than one in five of full-time students entering university drop out. These are mainly working-class students. The government has given universities almost £1 billion to support these students. But this is where illusion crashes into reality. A flaw in the system means universities are not penalised for recruiting students who do not graduate – providing they recruit even more to replace them and fulfil the government target of getting 50% of youngsters into college.

Like everything in our smoke-and-mirrors education system, this fails to address the real problem – bad teaching in too many state schools. MPs on the Commons public accounts committee last year discovered that maths students, for example, claim they are being forced to quit because they lack basic numeracy skills and so do not understand assignments and lectures.

Sir Richard Sykes, then rector of Imperial College, London, said: “There is a belief that there are thousands of kids out there who come from poorer backgrounds that are geniuses – there may be, but we can’t take them at 18 if they’ve not been educated.”

It is time the government stopped playing tricks and started examining why this is.

Minette Marrin is away

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