Pay more where supply doesnt meet demand
Currently we are short of science and maths teachers with a large % are 50+we are also short of teachers in places like Auckland. Your theory that changing tax will magically mean more teachers go to Auckland is unlikely to happen quickly enough. Why not simply pay teachers in subjects where there is a short supply more and have a realistic Auckland' weighting, to compensate teachers for working in Auckland - This should also apply to other core professionals, eg medical, after all its costs a lot more to live in Auckland than Christchurh or Napier.
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