Education providers are being urged to use mystery shoppers at overseas education fairs to check whether their agents are duping students.
The International Students' Association says the government acknowledges the problem, but action it has taken on immigration and international education has not cut to the core of the problem.
Its president Lukas Kristen said the association has been talking to the government and regional providers about agents.
Institutions needed to understand that students were not solely motivated by gaining residence nor were they there to make the institution money, he said.
Both agents and education providers needed to be honest with students from the start and not give the false impression that study leads to work and residence.
"If you look at an institution's website it's very aimed towards you working in New Zealand and you staying in New Zealand," he said.
"There's pictures of students, former students, working at farms, in Auckland in a business - and this is the international students' page.
"We've talked with a number of students that have been approached by international education agents overseas and when they ask the agent why are you pointing me towards this specific institution, the answer is basically this institution is paying me more money to recruit you."
Mr Kristen said that while universities were good and institutes of technology and polytechnics (ITP) were getting better, some private training establishments were still among the worst offenders. Some were run by one family with no governance structure.
One student was recruited by an agent to an ITP and told it offered an internship that would lead to work. The institute offered no such scheme.
Graduates either returned home after wasting their time and money, or entered into exploitative working situations to try to recoup something from a bad situation, he said.
Institutions needed to be clearer about what they could offer and a mystery shopper scheme would shine a light into what happens when students interact with agents.
A code of conduct from NZQA makes education providers responsible for the pastoral care of international students. Education New Zealand has also re-launched its Recognised Agency programme (ENZRA).
But International Standards for Education Agents (ISEA), which was created in October, said ENZRA recognised about 300 agents, a fraction of the thousands in use by New Zealand providers. Some Auckland providers were using more than 600 agents from one country alone, she said.
"It's the third time it has gone through such a programme and the industry has really kind of lost confidence in Education New Zealand to put together a programme that is going to fit the requirements of the providers," said one of its directors, Rachel Honeycombe.
ISEA aims to offer training, accreditation and a complaints service to act as a non-governmental regulatory body
"I think it's in demand now from the industry just to tidy up the sector," she said. "So we've had a good response from education agents themselves who are wanting to see the standard raised."
She said agents brought in more than half of all international students and she would eventually like to see providers refusing enrolment to people not on the programme.
Pii-Tuulia Nikula, a senior lecturer at the School of Business at the Eastern Institute of Technology in Napier, said while any move to improve quality was laudable, a non-mandatory scheme would be hard to implement.
Her research suggested current monitoring by education providers and the underlying techniques they use to do that are inadequate.
"How can providers actually find out how these agents on or offshore are actually behaving? Because otherwise their relationship is based on blind trust," she said.
Monitoring was confined to asking students about their experiences and data analysis such as visa approvals. Other providers might carry out a marketing audit or arrange visits to agents.
"What we basically found out is even if you use all of these monitoring techniques, the providers are not able to find out the true behaviour of their agents," she said.
Mystery shoppers were used in other contexts and would provide more reliable information, she added.
"We did find out that would actually help providers to find much more information about their agents than many of the other techniques," she said.