The unions claim to represent teachers' interests, but at what cost to pupils? (Reuters/Andrew Winning) 

One day, during my PGCE teacher training, we were all herded into a large hall where the teaching union representatives sat smiling behind their stalls. We dutifully queued up and signed on the dotted line. The option of not belonging was, in essence, hidden. We agreed to allow about £150 to leave our bank accounts every year because that's what teachers do: we belong to unions. Except for me, that is. I had to use the loo, was bored of queuing and left with the intention of signing up later. But when September came, I got busy working, and couldn't see the point of paying money to a union for nothing. In those first couple of years, every teacher who heard of my lack of protection from the big bad bosses (whom I have never met) rushed to warn me that I was putting my life in danger. Even if I didn't worry about being fired for incompetence, what if a child were to accuse me of something? Who would defend me? Eventually, I capitulated and signed up. 

In state education there is a kind of social obligation for a teacher to belong to a union. The most ardent union supporters among teachers belong to the National Union of Teachers (NUT). They tend to be very loud in the staff room, forcing others to toe the line. They push the mantra of evil senior management exploiting staff, and bully younger teachers to buy into it. The idea of holding colleagues to account or requiring high standards of teaching is not on their agenda. Good teachers keep their heads down, ignore the fact that they are paid the same or considerably less than the worst teachers, and get on with the job.

Interestingly, it is not just bad teachers who are vocal in support of union power. The union grip on schools, both psychologically and socially, is more pernicious than that. Some young teachers, good and bad, are radicalised by senior ones. The veterans seek out the more vulnerable and awkward young teachers, who may simply be looking for a club to belong to, or want approval, a voice, a reason to feel valued.

Most teachers believe fervently in their teaching union. If you ask them why, they will say something about being protected from evil management. If you're a bad teacher, there is some sense in this, for unions are powerful and will stand in the way of a head trying to get rid of a bad teacher. Heads know that firing a teacher is practically impossible in an ordinary school beholden to the local authority. It is estimated that in the last 40 years only 18 teachers — out of the 500,000 in the UK at any one time — have lost their jobs because of incompetence. Such is the strength of union power. Unions have persuaded most teachers — whether good or bad — that the protection of bad teachers is in the interest of all.  

In an academy which is independent of the local authority, unions do not have the same kind of power. Free schools are essentially the same as academies in terms of the freedoms they retain. Academies and free schools break up the monolithic structure of state education. Instead of taxpayer money going to the local authority, where bureaucrats decide how to use it in providing services to schools, the money is given directly to the schools, and heads decide how that money should be spent. Academies and free schools can set their own pay and conditions (thereby giving heads the option of rewarding good staff financially) and employ non-qualified teachers who have missed the PGCE herding-into-the-hall moment. With the centralised state education system broken up, unions will no longer be able to call for national strikes with ease. More importantly, they will no longer be able to protect bad teachers. A more open system will reduce union power.