A union's labelling the Education Minister's changes for reliever teachers a knee-jerk reaction to the current shortage.

Erica Stanford's changing who can gain a Limited Authority to Teach - allowing about 200 teachers who no longer hold registration to work as relief teachers.

It means both experts who aren’t qualified teachers and previously registered teachers, can come into classrooms as relievers.

PPTA President Chris Abercrombie says the change is essentially just putting in warm bodies to fill the gaps.

"They're looking after kids, not teaching kids or educating kids, not helping them - they're just looking after them. These kids deserve more."

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