Queensland schools run by the Exclusive Brethren which Prime Minister Kevin Rudd described as "an extremist cult" received more than $3.1 million in taxpayer funding this year.
The Brethren's Agnew School has 256 primary and secondary students at its Queensland campuses at Wakerley, Nambour, Toowoomba, Warwick, Maryborough and Bundaberg.
Former members say the group likes to stay separate from non-members and prevents lapsed members from contacting their families who stay in the group.
NSW Greens MP John Kaye obtained figures through freedom of information laws showing the Agnew School received more than $1.8 million from the Queensland Government this financial year and more than $1.2 million from the Federal Government.
Dr Kaye said there were six Exclusive Brethren schools, one in each state. State governments contributed more than $5.8 million this year to the schools and the Federal Government contributed nearly $12 million. Since 2001, enrolments at the schools had risen from 272 to 2100.
"State premiers can no longer hide," Dr Kaye said. "As long as these schools refuse to enrol children who are not members of the closed sect and as long as they continue to operate behind closed doors, there is no justification for the spectacular growth in public financial support."
A former teacher who worked at one of the schools said they discouraged tertiary studies.
"Board members remove pages of textbooks if they object on moral grounds to things like bad language or sex before marriage," the former teacher said. "They don't want their children to go on to university or other tertiary colleges because they might be corrupted."
He said the group had "extraordinary fund-raising capacity" compared with Great Public Schools (GPS) where he had worked.
"I can't understand how the school can be getting so much government funding when it has so much of its own money," the former teacher said.
Dr Kaye said Brethren schools received the maximum level of federal funding, usually reserved for schools in severely disadvantaged areas.
Fairfax journalist Michael Bachelard in his book Behind The Exclusive Brethren said a survey of members showed most were in "middle to upper levels of the socio-economic group".
Stephen Kirkpatrick, an Exclusive Brethren member and parent of four children at the Wakerley campus, said the group was "very family oriented" and "very protective of the family unit".
"We prefer that children stay within the group and marry within the group," he said. "They can do university or other studies through correspondence but we don't like them studying on campus because they are likely to become totally absorbed with that and become less involved in the family unit."
He said children used television and computers at school, but the internet had special filters.
Mr Kirkpatrick said the school received the funding it was entitled to.
