Federal ministers often reveal their inability to deal with complexities in their portfolios, none moreso than Coalition education ministers. Acting minister Stuart Robert has just demonstrated how things can easily unravel.

The ideological preferences of the federal Coalition are on their best display when their luminaries address independent or Catholic school conferences. After all, it is at such events that Tony Abbott declared that funding private schools was in his partys DNA, and Christopher Pyne denied that Australia had a school equity problem.

This time around, Stuart Robert managed to stick quite closely to his prepared script, but revealed his true colours in response to a series of relatively lame questions. Asreported in the_SMH_,Robert blamed dud teachers for the decline in the academic results of Australian students, while praising independent schools for employing only quality teachers and delivering a model example of education.According to Robert, a bottom 10 per cent of teachers were the key reason for Australias plummeting performance. But he assured independent school leaders he was not talking about their schools, because they did not accept dud teachers.

In one fell swoop, Robert managed to thoroughly immerse himself into the morass of Australias unlevel playing field of schools. Most non-government schools operate under markedly different obligations and rules to the government sector, managing to turn choice of schools into a schools choice of preferred inputs, including teachers. Even though non-government schools enjoy significant resource advantages, they can also pick and choose their students when the going gets tough, they send the kids to the public school down the road. Even a moderately capable minister might pause to ask why this is the case and how it might contribute to the problem. A smarter one would have considered the likely wider impact of his rush to judgment.

Stuart Robert is no stranger to controversy, his string of accomplishments includes at leasthalf a dozen own goals. This time around heignored one piece of sage advice: better to remain silent and be thought a fool than to speak and to remove all doubt.Both the SMH andThe Guardianreported some of the reactions to his comments. A previous NSW Minister, Adrian Piccoli,saidit is factually wrong to blame dud public school teachers for the decline in the academic results of Australian students. Weve got this very long underperforming tail, but the biggest decline is in high-performing students not doing as well as they used to. A large chunk of those high performing students go to independent schools and selective government schools.

There is no doubt that poor teachers can impact negatively on student outcomes, and school principals are keen to either see them improve or find a different job. But Mr Roberts bottom 10 per cent of teachers doesnt seem to affect one sector more than others. Weve long known that comparisons of schools enrolling students from similar backgrounds the only valid way to compare schools reveal that thepublic and private sectors perform at similar levels. It seems that Mr Roberts bottom 10 per cent remains widely distributed. Perhaps all schools, occupations, parliaments and indeed gatherings of ministers have a bottom 10 per cent.

Whats really remarkable, and deserves closer examination, is the failure of non-government schools to achieve better student outcomes despite the resource advantages they enjoy (including the ability to offer teachers more money and less challenging students).

But the good minister has a solution:improve what and how students are taught. Nothing new there:his infatuation with curriculum (aka cultural warfare), teacher training, performance and achievement doesnt differ greatly from the priorities of his predecessors. Its remarkable that such a consistent focus hasnt yielded results, but then again ministerial responsibility and accountability doesnt extend to serious and long-term evaluation of the fetishes of particular ministers. The man who wants to sack teachers will be long gone and forgotten, and within a few years another minister will do it all again.

Teachers have longer memories; they have always been in the firing line. Weve had a score of inquiries into teacher training and/or performance over the last couple of decades. Each new minister acts out Einsteins definition of insanity: doing the same thing over and over, and expecting different results. Its easier than tackling the tough structural issues. It would be interesting to see how he might replace the ten per cent he would sack. Or how he might actually make a constructive contribution to solving the chronic teacher shortage that currently exists, and which is compounding the challenges that teachers and principals face. Ah, but thats not Stuart Roberts problem, as successive federal ministers have been keen to stress: they dont run schools!

Few education ministers see the impact of teachers in a wider context. Teachers are always critically important, but other impacts on achievement are readily apparent. The Gonski review clearly cited research confirming that the socio-economic status of a school affects the performance of individuals within that school, irrespective of their own socio-economic status. As Piccoli says,teachers are the biggest in-school factor, but parental background and socioeconomic status have the overall largest influence.The obvious implications are that efforts to improve overall student achievement should not be confined to the classroom and school. Addressing one set of impacts, to the exclusion of others, lies behind our path to failure.

Tom Greenwell and Chris Bonnor are the authors ofWaiting for Gonski: How Australia failed its schoolspublished by UNSW Press.