The Key/National programme depends for its rationale on a theory and practice developed first in the US. It's that the goal of education is to prepare young people for the world of work, holding out the carrot that the better the education, the better-paying the job attained.
From that theory flows the belief that if children aren't learning, then it's the fault of the teachers. And consistent with the business-orientation of this model, the best way to find out just which teachers are most blameworthy is by subjecting the students to standardised testing and then measuring the quality of the teachers on the basis of the results of the testing of the students. Once the poorer teachers are replaced, the full benefits will flow to the students' achievement and ultimately to their economic advancement.
The trouble with this approach is several-fold. As a practical matter, it's been tried in the US for the past 10 years and failed spectacularly. When the teacher's performance is measured by her student's test scores, it becomes a matter of survival to teach to the test. And since the quantitative models don't apply to art or music, those "accessories" are soon dispatched. In some American cities such as Atlanta and Dallas, the cheating by desperate teachers and administrators has led to scandals and criminal sanctions. Worse, the performance of poor and minority students has not been improved.
This one-dimensional approach of National's doesn't address other important bases of poor educational performance than teaching, such as poverty. As one critic put it, "the people who say poverty is no excuse for low (academic) performance are now using teacher accountability as an excuse for doing nothing about poverty".
And then there is the question of education's goal. Beyond its mercantile possibilities, education ought to help make a person into a better citizen, by providing the tools for critical thinking and engaged exposure to help foster and develop curious minds in our young people.