Every time I consider voting for David Cameron, he makes a pronouncement on education and I wince. One of his recent ones was that the teaching force should consist of graduates with no less than a 2.2 degree.
The finest teacher who taught me at secondary school had no degree at all. My wife struggled with maths and the struggle stood her in good stead when she became a teacher, because she understood why children encountered difficulties with the subject. Through her patient explanations, one of her pupils who also hated maths eventually became an accountant. And I know a teaching assistant, who achieves excellent results with the children, without a single GCSE.
So making sure every entrant into teaching has a top-quality degree is a bit of a daft idea. But then, what initial criteria should you use when trying to decide who is suitable for teacher training, and who definitely isn't? Frankly, I think much of it must come from the initial interview.
Some years ago, a London university invited me to be a member of the panel interviewing prospective candidates, but after half a dozen sessions I couldn't stand it any more. Why? Because the panel, consisting mainly of crusty academics or wacky lecturers who hadn't kept up with what was going on in classrooms for centuries, seemed to have no idea what it was looking for.
Even now, I maintain there is something special about a person who is going to become a really effective teacher. There's an immediate charisma, a sense of humour, a burning enthusiasm but a certain humility, a passion for learning, a love of being with young people. When I'm considering a candidate for a teaching position at my school, I usually know within 10 minutes whether I'm going to be interested.
We take many students from a local university at our school, and I remember one particular group of B.Ed students who arrived for their first teaching practice. They were bright, alert, asked lots of relevant questions, and I sat talking to them for far too long. I felt they would all be successful, but one stood out. She'd become disenchanted in another profession and felt that primary education might be her forte instead - and there was something about her that made me feel we might have found a gem. After a blindingly successful practice, I told her I'd be phoning her in three years' time to offer her a job. She's been with me ever since and is one of the best teachers I've worked with.
But although we've had many first-class students, we've also had our share of those who should never have been offered college places. The poor lady who was terrified of talking to a class; the boring young man with no humour whatsoever and who was only doing the course because he couldn't think of anything else to do; the woman who burst into tears every time the class teacher asked to see her planning; the student who kept turning up at 9.10am because she had difficulty getting out of bed; and the slightly unsavoury character who, when he found out I was a film buff, offered me rip-off DVDs of recent movies.
Ultimately, though, you can't make a blanket rule and expect it to work all the time. As a young teaching deputy head, I remember being given a very timid student who was thinking of giving up and doing something else. Then I found out she'd had a dreadful previous experience at a chaotic school and once I'd bolstered her confidence she had a stunning practice and ultimately became a highly successful headteacher.
Which proves it's all about far more than a few paper qualifications.
Mike Kent is headteacher at Comber Grove Primary, Camberwell, south London. Email: email@example.com.