Politicians are demanding answers from education bosses over just what the secretive Gloriavale school is teaching girls.

The Education Review Office is being hauled before a parliamentary committee this month, to explain why the extreme fundamentalist school is allowed to stop education early and steer all pupils towards life in the community.

Green MP Catherine Delahunty has requested the briefing.

She's concerned the school's curriculum prevents pupils, especially girls, from going on to tertiary study.

"I just don't believe that every girl wants to have babies under the age of 20, and wants to be a domestic worker. I don't believe every boy wants to be a farmer."

"My understanding is that they don't really encourage tertiary study, and I think those boys and girls need those options." 

She understands the highest level of secondary learning is NCEA level 1, and that there's a strict divide of subjects girls and boys can study.

In its latest review, ERO found little fault with the West Coast school, saying the tuition standard was suitable for teaching its curriculum.

A spokesperson for Gloriavale made no comment when approached by Newstalk ZB.