Cellphones will be banned from schools if the National Party is elected in October, but the Secondary Principals Association says the plan is unworkable and unnecessary.
National Party leader Christopher Luxon told Morning Report the ban is one of the ways the party would lift "abysmal" achievement in New Zealand schools.
Declining achievement in schools has raised alarm in recent years and last month official figures showed 15 percent of school leavers in the past year did not have any NCEA qualifications.
Last month the UN also released its report, Technology in Education, and found cellphones distracted students and had a negative impact on learning in the 14 countries studied as part of the report.
"What are common sense practical ways to improve student learning? One of them is to actually ban mobile phones," Luxon said.
"What we're hearing from parents and teachers and what we're seeing in the research is that phones are incredibly distracting and disturbing and they are getting in the way of student achievement."
Luxon said some schools were already enforcing bans well already.
He pointed to examples of students leaving phones at reception and then retrieving them at the end of the day.
"Other schools actually drop them into pouches in their homerooms, [at] other schools the phones must be off and put away in bags and they're away all day."
Countries like Australia, the UK and Canada already had similar bans in place which worked, Luxon said.
"We've seen that in Australia where they've implemented something similar in all the states ... and it's worked well."
When asked why there was a need for a ban and another layer of compliance when some schools were already enforcing a no-phones policy, Luxon said he had been told by principals that a nationwide ban would help.
"Not all schools are doing it and actually some principals have come in and said 'it makes our life easier if you come in and actually do that as a nationwide ban'."
But Secondary Principals' Association president and principal of Papatoetoe High School Vaughan Couillault believed the plan was not necessary.
"[There's] not a whole lot of students walking around at interval and lunchtime, banging into lamp posts and buildings because they're totally distracted by their cellphones.
"Actually what's best is to empower schools to make decisions that are right for them and their community.
"I don't think central [government] controlling banning is the way forward."
Students were not allowed to randomly use their phones at Papatoetoe High School, there were situations where it was appropriate to use them, said Couillault.
"In some lessons they're away and you don't see them the whole lesson and other lessons they might be engaged in videoing [a classmate] doing a speech or performing at sport.
"A piece of legislation that bans [phones] won't instantly stop [inappropriate use] overnight, it will create conflict, it will create a legal requirement for us to confiscate rather than to educate and train students on how to use things appropriately."
Then there were the practicalities of enforcing a ban with smart devices like watches, he said.
"The practicalities, particularly in a large urban high school, of taking devices off students en masse are just not worth thinking about."
Couillault gave the example of Mt Albert Grammar which has 3000 students.
"If it took one minute to take a phone and process it off a student at the gate, that's 3000 minutes of human resource to get everyone's phone off them in the morning, 3000 minutes in the afternoon, 6000 minutes of phone policing, there's no time for Maths and English."
But Luxon dismissed that.
'This is not rocket science ... If a school principal can't work out how to actually comply and enforce with the programme, there'll be some other issues going on in that school."
Defending the plan when speaking to reporters on Wednesday afternoon, he said the research from UNESCO and other studies in the US and UK was clear, showing academic achievement improved by 6.5 percent, or an extra five school days.
"The research is obvious ... it's actually what's needed to make sure that there are no distractions inside classrooms, that learning can be optimised and take place.
"This is not political, it is not ideological, this is just simply us saying 'we have a problem, let's define our problem in education realy clearly: poor academic results in student achievement - and then let's work up practical, common sense, pragmatic solutions."
He said it would be implemented with a simple regulation under the Education Act.
"Schools will then have to comply and enforce that, it'll be audited and compliance checked through ERO as per normal. There are a lot of regulations schools have to comply and enforce with, this'll just be one of them."
'It's really helped me to focus more' - Wellington Girls' College student
Wellington Girls' College year 12 student Tessa Gilhooly told Morning Report that school rules recently changed around phone usage and it had made a difference.
She said mobile phones now have to be stored away during class, only to be taken out during interval and lunchtime.
"We walk in and there ... a pocket thing on the wall and everyone has to place their phones in."
Gilhooly said the teacher then counts the number of students compared to the number of phones to ensure everyone has put theirs in.
"It's really helped me to focus more and I think it's a really good move.
"[In] the beginning I had a bit of a negative reaction but the experience has been really positive so far."
But she was against a blanket ban where she would not have access to her phone the entire day.
Phones were useful for taking photographs of notes on the board and taking a break on your phone during interval and lunchtime was necessary for her brain to focus, Gilhooly said.
Wairarapa College principal Matt White told Nine to Noon his school imposed a ban on cell phones at the start of the year and the response from staff and the community had been overwhelmingly positive.
The school had been experiencing problems with students' phone usage prior to that which he had first hand experience of when he was teaching a class last year, he said.
"Just the constant checking of their phone, checking it for messages, going on social media, messaging groups, that it was almost a habit that every opportunity a student could have they were checking their phones and that was widespread from Year 9 to Year 13."
The school's policy means that phones cannot be used or seen during the school day and that included both break time and class time, he said.
Banning phones during the breaks made it easier for staff to manage the policy and stopped problems with bullying via social media, he said.
But White said he did not think the government needed to mandate a ban on cell phones and every school should be able to determine it for themselves based on meeting the best needs of their community and their young people.
Christchurch's Hillmorton High School is in its third year of banning phones at school.
Principal Ann Brokenshire said the school's board voted to introduce the ban after consultation with students, staff and whānau at the school.
Initially students did not like the change, but most readily accepted it, she said.
"It changed the culture in the classroom almost overnight."
Previously the part of a class would be spent by the teacher trying to get students to put their phones away and then that would happen in the last five minutes of the class too, she said.
"So that doesn't happen any more at all. So I think probably in terms of teaching and learning, that's the biggest change."
Students are less willing to ditch their phones during breaks and still often request them at that time, but the school's complete six-hour break from phones stands, Brokenshire said.
There will still be about two phones confiscated from students each day in a school of about 1200 students, but the vast majority of young people do comply with the ban, she said.
'They don't need Christopher Luxon's permission' - Hipkins
Labour leader Chris Hipkins said it was schools' boards of trustees who should be making the decision on whether to ban phones.
"Schools have the ability to ban smartphones or use of cellphones in school now, they don't need Christopher Luxon's permission to do that," he said.
"Those schools that have banned cell phones I've fully supported them previously as minister of education and as prime minister ... those school boards of trustees represent the parent community, they can make their own decisions, they don't need central government dictating to them what they should be doing or how they should be doing it."