The poll was organised by Year 13 students Noah Atchison-Darby, Nikki Chapman and Yuong Chaiyaklang.
"The flag is an important part of our country and our culture," said Noah.
"It's important to know what youth think about changing it."
It was also a good learning experience because it showed students what voting in a real election was like, Nikki added.
Springbank students quizzed by the Advocate had strong views.
Kaeo's Keela Cashmore, 12, wanted to keep the current flag.
"John Key's trying to make a mark on history and I think it's a waste of money. If there were better designs [for the shortlisted flags] I might have agreed to it, but they don't really speak for New Zealand."
Alisha Tahere, 13, of Ohaeawai, also opted for the status quo.
"Our men fought for the flag, and were buried under it, so changing it would be pretty rude."
Kurtis Foster, 16, of Okaihau, said New Zealand had changed a lot as a country and the flag should reflect that.
"I feel we shouldn't have the English flag on it. We're independent, we're not a colony, and the silver fern represents New Zealand. When we wave the current flag at sporting events people see the Union Jack and think we're English."
Kerikeri's Mike Michaux, 14, said changing was an unnecessary expense. He liked the Union Jack on the flag because he was born in England.