Hugh McClure, a student of Smith's Hill High, said students were "scared" of the prospect of rising tertiary education costs partly because it would affect their ability to change courses.

"We don't know exactly what we want to do in future," he said.

"Because the cost is so high, many of us could not go to uni at all for fear of wasting ... money by changing degree halfway through.

"That would be the greatest of travesties - if people weren't attending university because of this."

The rally, at the University of Wollongong on Thursday, attracted about 70 students, staff, union figures and politicians, who marched across campus to protest the federal government's proposed changes to higher education.

Organiser John Passant, a casual tutor in the school of Humanities and Social Inquiry, told the rally university degrees should be free.

"If it's the community and business that are getting those benefits of higher education, maybe it's business that should be paying for higher education and not students," he said.

Last month, the University of Western Australia became the first in the country to reveal how its fees would look under a deregulated system.

There, the cost of a law degree would rise from $82,198 to $95,220 and the cost of a teaching qualification would rise from $30,544 (for a bachelor's degree and a two-year master's) to $60,000.

The government is expected to scrap one of the most unpopular aspects of the reforms - the plan to apply real interest rates to student debts - on the advice of the architect of the HECS repayment scheme, who said it was unfair to poor graduates.

Cunningham MP Sharon Bird, addressing Thursday's rally, said applying interest to the debts would have flow-on disadvantages for other, less well-off parts of the community.

"I think it will put real pressure on people who graduate and want to work for community and not-for-profit organisations to then rethink that decision, because it's going to have a significant financial cost for them," she said.