So another term ends with a quick bout of finger-wagging. “Good as our teachers are, they must be better,” says shadow education secretary Michael Gove. With teaching apparently the must-have career of every graduate, the Conservatives propose raising the bar, making it harder for people to train as teachers in England. Under a Tory government, the minimum entry qualifications for primary teachers would rise from grade C GCSE in English and maths to B grades. A degree at 2:2 level or above would become the minimum for all teachers.

This idea was announced shortly after Ed Balls, the Schools Secretary, had unveiled the “teacher MOT” as part of a flurry of white paper proposals. The Government wants teachers in England to have a licence to work in the classroom which will have to be renewed every five years. Mr Balls described it as part of an “uncompromising approach to school improvement” and said the checks would make sure schools were “facing up to inadequacy”.

All this has a kind of logic. If the thesis of government adviser Sir Michael Barber is right - “the quality of an education system cannot exceed the quality of its teachers” - then it makes sense to improve recruitment and training.

However, more than 12 years into a Labour government, this feels not so much like shutting the stable door after the horse has bolted as suddenly remembering that there’s a stable.

After all, there have been plenty of other attempts to improve the quality of teachers’ work over the past decade. Multiple incarnations of performance management, advanced skills and excellent teacher schemes, threshold assessment, the upper pay spine - weren’t these all designed to reward good teachers and, at the very least, not to reward poor ones?

Is teaching better as a result? And will it be better as a result of the latest bit of workforce remodelling - the “rarely cover” rule? In hindsight, it looks as if ministers’ bids to reform the workforce lacked a clear focus on classroom impact. Tough talk has too often translated into structural changes that simply get in the way, as with teaching and learning responsibility payments. And this may prove to be the case again with rare cover. It’s as if the Government sometimes worried about upsetting us.

Take the “social partnership” between government and most of the teacher unions. In unveiling its long-standing commitment to “workforce remodelling”, this group makes statements that are hard to disagree with. There’s all but a whiff of home-baked apple pie about comments like this: “It’s widely accepted that covering for absent colleagues is not a good use of a teacher’s time. Schools that have low or no teacher cover report happier staff, teaching better lessons” (workforce agreement, Training and Development Agency for Schools.)

As a result of the national agreement in 2003, teachers haven’t had to undertake routine administration tasks such as collecting dinner money or doing displays. They haven’t been asked to invigilate exams. And, from September 2009, they won’t be required to cover for absent colleagues except “rarely”.

You don’t have to be a fresh-faced management consultant to wonder whether an opportunity wasn’t lost in all this reform. If teachers aren’t collecting dinner money and doing their own photocopying, what are we doing instead to improve our teaching? Of course, there is the planning, preparation and assessment to do. But that isn’t the stuff that makes teachers teach better. Again, as Sir Michael tells us, better teaching means being better at instruction.

Where was the requirement for teachers to use non-contact time to observe colleagues, for mentoring and coaching, to ensure training was embedded into the day job rather than pigeon-holed in after-school meetings or “Baker days”? Where was the overhaul of teacher training to make sure new entrants are learning the “craft of the classroom”?

It may be the same with rare cover, which could end up taking away from schools more than it gives us. For pupils and teachers, the things that make school life special and memorable are often those that lie beyond the classroom and which may occasionally require cover.

It is naive to propose that a school trip should be accompanied by an administrator, teaching assistant or parent. Trips are a chance for teachers to help pupils to relate what they see in the wider world to what they have learnt back in class.

The hard line on teachers doing any cover may rebound on pupils who find themselves in a group where their teacher goes on long-term sick leave. It is hard to see where the Every Child Matters agenda is in a succession of cover supervisors or supply teachers.

Thus, the rare cover concept reminds us that something which seemed sensible in a committee room in Whitehall may not have the desired effect in schools. As with so much of workforce remodelling, the aim may not have been used sufficiently to drive improvements in how we teach.

And perhaps more depressingly, there is one other key ingredient that has been left out of the grand plans: the impact on the child.

Geoff Barton, Headteacher, King Edward VI School, Bury St Edmunds, Suffolk.