"I don't agree with the assertion put forward by the principals that this Government is placing too much emphasis on the voices of young people in this process. I think young people's futures are what we are taking about and they have every right to be heard in this."
The principals' spokesman, Glen Dunham of Massey High School, said the Minister's office had been contacted and the group was happy to meet the minister in Wellington at any time.
He said said they were from a mix of deciles and while they agreed NCEA needed to be reviewed, professional educators had to be at the heart of that.
"Principals are appalled at the lack of consultation and how this bizarre process is going to hurt the life prospects of a generation of young New Zealanders."
One of the gripes is that Hipkins had met with few principals, yet the process included a contest to encourage students to have a say, involving prize money.
They asked Acting Prime Minister Winston Peters to step in, halt the review and begin again on a process that more fully involved boards of trustees, principals, teachers and parents.
The 23 further principals to sign up to the group include those from Northland College and Whangarei Boys' High School, Rotorua Boys' High, St Peters in Cambridge, two schools in Wellington, and others down to Invercargill.
The original 37 principals were all from the wider Auckland region and a mix of state and private schools. Hipkins had described the principals involved as having a "traditional" approach to education.
Asked about that by National's education spokeswoman Nikki Kaye in Parliament, Hipkins said it was "a factual explanation of the views of some of the people".
"I want to be very clear that there is nothing wrong with that, and I believe that traditional voices need to be heard in this process. Other voices also need to be heard."
He said until the group took out advertisements in the Sunday papers he had not heard from them. He said he had meetings scheduled with the Secondary Principals' Association which would be attended by more than 100 principals and the Secondary Principals' Council had provided feedback from about 50 principals.