Opposition parties and a teacher union suspect there is a hidden agenda behind the school closures and mergers in Christchurch.
Ministers announced on Thursday 13 schools would close and 18 others would be involved in mergers as part of a $1 billion rebuild and realignment of education in the city.
They say rolls have fallen and populations have shifted since the earthquakes, but critics believe cost-cutting is one of the reasons for the shake-up.
Primary teachers' union president Ian Leckie says hundreds of jobs will be lost if the closures go ahead.
"This is unprecedented, it's on a mammoth scale," he said on Radio New Zealand on Friday.
"The government has taken the opportunity to save money by merging schools in parts of the city that weren't damaged."
Labour's earthquake recovery spokeswoman, Lianne Dalziel, says the decisions are a sign of what could happen in the rest of the country.
"The government is using Christchurch as a laboratory, this isn't just a response to population change," she said.
The Green's education spokeswoman, Catherine Delahunty, is also suspicious about the government's intentions.
"There is real concern that the government will take advantage of the disaster to `supersize' schools and carry out their undermining of the public education system," she said.
Teachers and the opposition parties are also "appalled" by the botched announcement about the future of Shirley Boys' High and Avonside Girls' High.
Thursday's announcement put them in the list of possible mergers but both are waiting for geotechnical reports before any decisions are made.
"To make the announcement and then backtrack is insensitive, it's absolutely appalling," Ms Dalziel said.
The ministry on Friday blamed "some media" for inaccurate reports but has issued an amended announcement.