Critics say the increased gap, widest in our poorest areas, shows low-decile schools are guiding students into 'softer' subjects and therefore limiting their careers to make pass-rates look good.
However, principals from the schools in question say they try to ensure all their students go on to meaningful education or employment.
Papatoetoe High principal Peter Gall said while they had about 50 kids a year go on to university, their focus was primarily on NCEA Level 2, which would get students into good courses but also built a platform for going on to Level 3.
"A lot of our students in Year 13 are not doing UE. But what does university entrance actually mean anyway? To me it's almost a pointless exercise now."
He said some of the universities, like Auckland, had higher thresholds, while other institutions were struggling for students and would allow people to come in with lower marks.
"When they can make their own rules, you've got to ask, is it actually needed any more."
John Heyes, from Mangere College said it was "perplexing" that in 2015, UE should still be seen as a desirable target for all senior secondary school students.
"It is well and truly time for this perceived primacy of UE to be placed in its proper perspective as the necessary qualification."
But at least two principals said it was dangerous every time a student took a course that wasn't UE-approved, as it limited their future options.
"It's not about university being good or bad," said one of the principals. "It's about if we are making the decision that these kids aren't capable of going to university."
"There's a risk that assumptions are made that because they're Pasifika and other people have low expectations they won't pass."
Mentors who have worked with Maori and Pacific students say expectations were a key factor in success, and should not be undervalued.
Ant Backhouse, national director of the I Have A Dream programme, said sometimes schools needed to take risks on kids and put them in tougher subjects despite it reflecting badly in final marks.
"It does happen that schools put students in subjects they know they will pass," Mr Backhouse said.
"Any multicultural high school you go into, go into a travel and tourism class versus a physics or biology class — you definitely see the brown faces versus the white faces."
Backhouse said often students were left to make choices with little guidance.
"And often they are making those decisions about university versus vocational study at a very early age. If they change their mind at Year 12 or 13 it's too late."
