Principals the Herald spoke to yesterday defended charging students subject fees, saying Government money did not stretch far enough.

Rangitoto College principal Allan Peachey said almost every student paid the school donation and subject fees.

But he said schools faced different pressures and it was vital people understood the cost of education.

Government funding had not kept pace with the range of subjects on offer and changes in teaching methods.

"The old traditional textbook-copy-it-off-the-board is no longer appropriate, yet from a Government funding point of view we are still funded that way.

"It's all very well to talk about free education. Free education is delivered very well in this country to a certain point. If you want to enhance education beyond that, there's a cost and somebody has to pay that."

Massey High School principal Bruce Ritchie said subject fees had been accepted by parents for some time.

"Charging is legitimate for materials that become the property of the student ... you can't supply all that free of charge - you just can't.

"There's nothing new, it's always happened."

Long Bay College principal Stephanie Norrie said her decile 10 school did not get enough Government funding to meet community expectations.

"People perhaps need to accept the reality that education in New Zealand has not been free for a long time. There have been expectations on parents to supplement Government funds for a long time."

Tom Robson, president of the Secondary School Principals' Association, said schools faced an ongoing battle trying to stretch budgets to "reach every point of the compass".

The law prevented schools from demanding a donation and no Government had been prepared to change that. Schools had to grab any opportunity they could for "cost recovery".

"If you have free education in this country, someone needs to define what that means. If it means that anyone can come to a school and take any course they like at no cost, then those courses have to be resourced properly."