The Government gave permission for four new charter schools, or Partnership Schools, to open this year, bringing the total in New Zealand to nine.
Of the four schools that opened this year, all are at least 15 per cent down on target numbers. Pacific Advance Senior School, in South Auckland, needs 40 more students to meet its roll target, called the Guaranteed Minimum Roll (GMR).
Two of those that opened last year were also not at capacity, including the struggling Te Pumanawa o te Wairua in Whangaruru, and The Rise UP Academy in South Auckland.
The GMR dictates the schools' funding, which they get in bulk per year, unlike state schools, where student funding is quarterly.
The schools are supposed to be funded at rates comparable to similar-sized state schools but having less than the targeted number of students pushes the per-pupil funding level up. As it stands, per-student funding at Pacific Advance is around $25,000. An average state school is $7600 per student. Smaller schools would cost more. Figures exclude property and central-funding costs.
The chairman of the school's sponsor, the Pacific Peoples Advancement Trust, Michael Jones, said the school was confident it would reach 100 pupils before the end of the year.
"We had to be realistic with the timeframes from the time we were successful as an applicant in late October through to opening the school in February," Mr Jones said.
"We had to open school and position our kaupapa into the community - and it's a big call for families to pull their students out of schools."
The school solely targeted Year 11 this year, and would accept older students from next year.
Alwyn Poole of Villa Education Trust, who runs the new Middle School West Auckland, said he was confident of reaching the target roll figure. Villa's first charter school, in South Auckland, was full this year.
Post-Primary Teachers' Association head Angela Roberts said the low take-up showed the schools were not offering anything new. "I'm not surprised there seems to be little parental demand because we already have Maori and Pacific immersion, just like we already have services academies."
Labour said the schools were getting "preferential treatment" while the Greens said they were not the "game changer" they were promoted as.
Act MP David Seymour said the figures were not worrying, and many new schools, including state schools, opened with below-target numbers. He said while it would be difficult to attract more students as the year progressed, the schools were working with the ministry and it was clear that meeting their roll numbers was a requirement.
Early this year, the Government intervened at the charter school in Whangaruru, partly because of low roll numbers. However Mr Seymour said it was unfair to compare Whangaruru with other schools as it also had other issues. Those included truancy and a lack of governance.
The Ministry of Education said there were no penalties for failing to meet roll targets as numbers were not a performance measure.