National is calling for "balance" in content used in school exams that might be deemed political.
This year's NCEA level 3 English exam asks students to analyse a 2017 article from NZ Geographic about water quality and farming.
The question has National MPs fuming, agriculture spokesperson Todd Muller saying it promotes an "insidious narrative" and portrays farmers as "environmental vandals".
"In my job I get out and talk to farmers very regularly, and they are feeling incredibly beaten up by this Government and a sentiment that they feel in the country that's very much against them," he told Newshub.
"Where have we got to as a country where farming is now condemned as opposed to celebrated? The examples you see in school exams, they're all on the condemnation side - not on the celebration side. I call for balance, and it has to happen."
National MP Amy Adams even called it "state-sponsored bullying and brainwashing on a massive scale".
But the editor of the magazine which originally published the article has defended it, challenging "anyone who identifies incorrect facts in this extract to write to me for a correction".
"Brainwashing turns out to be really easy if 'identifying environmental issues' is all it takes," Rebekah White wrote on Twitter.
"At the time it was published, the feedback we received from dairy farmers was overwhelmingly positive."
Muller suggested the question should have used an essay focusing on "what's being achieved".
"No one's suggesting that you don't have a conversation with our young people in terms of streams and rivers and the pressures that they're under, but where is the focus on what's being achieved?"
One student told Stuff's National objections to the question were absurd.
"They had an economics question this year about the removal of a petrol tax, so I don't think politicians should be too concerned about any biases that NZQA might or might not have."