As New Zealand edges towards shortages of secondary teachers in some regions and subject areas, it's worth considering what the impact of this will be on students.
Experience in schools tells us that students don't do as well when they don't have people skilled in their subject area teaching them. And in the voluminous PISA 2012 reports there's real evidence of this, and evidence that it was happening in some areas of NZ even then, when recruitment issues were less than they are now.
Worst of all, the impact of shortages of specialist teachers is felt heaviest on the students who need the most support and are most at risk of not achieving.
This report is primarily about maths achievement, one of the areas that principals are increasingly reporting they are having trouble recruiting suitable teachers.
Now correlation is not causation, and this report doesn't claim that the difficulty recruiting teachers of maths in low SES schools leads directly to lower achievement. But the fact that at that point in time principals in low SES areas were more likely to report difficulties recruiting in specialist areas should have been cause for concern to the Ministry and Minister.
A Ministry of Education survey at the start of 2014 showed that 47% of secondary jobs were advertised more than once. This seems to signal a fairly widespread supply problem, and there is no indication that things have improved since.
How we go with this year's STCA round could have a big impact on this. The relativity of teachers' earnings to other jobs matters for people who have other options. Teachers have not just been falling behind inflation as we all know, but our wage growth has been slower than average increases in the private sector. Earlier this year Bill English said we are looking at average wage growth of 2.9% a year for coming years.
If this government is happy to let teachers earnings shrink relative to both inflation and other professions, then they should expect to have increasing problems recruiting teachers. As PISA warns, the impact of this on students won't be good, and it will fall disproportionately on the students who need the most support.