An immigration lawyer has likened some of the commission-based practices in the international student sector to a Pyramid scheme.
International students pump more than $4 billion into the New Zealand economy every year and almost a third of them are from China.
Education agents say the sector is wide open for the exploitation of Chinese students.
Amy, whose name has been changed, said she was shocked to learn about practices she said are used commonly in New Zealand.
The Chinese national doesn't want to be identified because she is terrified of the consequences of speaking out.
Towards the end of last year she started working as an education agent.
Agents work for commission in the private sector advising students what schools and courses there are in the country.
Amy said often students from China did not have the English level needed to enter tertiary institutes so education agents arranged for staff or someone else to take internal English tests for them.
"Then the students can't keep up, often fail and a lot of education agents will help them to switch schools and make more money," she said.
"Three weeks into working at the agency last year I was asked to take the test for someone else by my boss.
"That was the only time, so that's why I'm still with that company."
Another education agent, who worked as an intern, said she left after three months largely because of what she was being asked to do.
She also doesn't want to be identified, but said she was asked to take English tests for students up to three times.
She was also told to write essays and correct homework for them.
"I didn't feel comfortable doing that at all but I felt pressured by my boss," she said.
"I know of other agencies who also push students towards a particular school because they know they get more commission from them."
Kerwin, a student who arrived in the country from China three years ago, said he felt played by his education agent.
He told his agent he wanted to study at a reputable school and was sent to the New Zealand National College, which has since been shut down by the Qualifications Authority for poor quality control.
"They tell me 'we [have] a new school for you to go to, you can study a business diploma, it's easy for you to study and easy to go to university [after]'," he said.
Kerwin said did not trust education agents anymore.
Immigration lawyer Alastair McClymont said these kinds of practices were prevalent in the Chinese student market in New Zealand.
"Quite often what they [agencies] will do is they'll have a student [and] they'll turn that student into a sub-agent, who then goes and recruits other students and gets commission," he said.
"It's kind of like a pyramid scheme, one student will come, bring another five students and they'll get paid a percentage."
Kerwin, both education agents and other students RNZ has spoken to said students from China were often young, vulnerable and believed education agents had their best interests at heart.
There should be more regulation in the industry in New Zealand, they said.
Education New Zealand, the crown agency that promotes education to overseas students, said it did recognise some agencies.
But it does not know how many education agents there are in the country because they do not have to be registered.
The Qualifications Authority said it was not aware of agencies using staff to take English tests but that would be a significant breach of conduct.
Last year it reviewed tertiary institutions approved to provide their own internal English proficiency tests and found the vast majority of the assessments weren't up to standard.
As a result it expects to make a decision next month about whether to remove internal tests altogether, meaning students would have to take internationally recognised tests instead.