Students' grades in the paper will be counted towards NCEA.
Mr Thornton said while last year the students trialled the test on a computer, this year they were also trying touch-screen tablets that could change finger scribbles to text.
He said 30 per cent of schools had tablets, while others used systems based around a keyboard and mouse.
"Our thinking down the track is that the input needs to be device agnostic. It shouldn't matter what you've got - the software must be capable of taking on any of those."
The NZQA would also trial a digital listening test for languages this year. Another project was looking at special assessment conditions for students with learning issues like dyslexia who would normally use a reader or a writer.
It meant they could highlight and replay text as many times as they wanted, and eventually would be able to sit in the same exam room as other students.
Eventually, digital exams would be compulsory across schools.
Secondary Principals' Council chairman Allan Vester said there would seem to be some advantages to going online, but the sector needed to ensure it was used as an opportunity to move to assessing 21st century learning skills.
"We need to make sure that the assessments are driven by the curriculum and learning, not by the ability of the technology to carry out the full range of assessment tasks."
Mr Vester and Secondary Principals' Association New Zealand president Sandy Pasely were concerned about access to technology.
Ms Pasely said the policy needed to be well resourced and right for all schools, not just those with good technology access.
"Have they considered the hardware needed, the tech support, WiFi speeds around the country, and the skill levels of different children?" she said.
"We already have issues with listening just with CDs. So there are a huge number of issues that have to be worked through.
"The sector needs to be reassured about this."
NZQA will embark on an information campaign in schools this term.
Online option a hit with girls
It took a while for students at St Cuthbert's College to get the hang of doing algebra on a computer - but it did save them from sore hands.
A small group of pupils at the Auckland girls' school were some of the first to sit a maths exam online last year, as part of a national pilot.
"It was really different to doing it on paper, but it was a lot faster for us and for the teachers to mark too," said Francesca Orchard-Hall, 15.
"For questions that needed long written answers it was really nice not to get a sore hand."
Sophia Yang, 15, said the software was so efficient she actually finished her exam early.
"We got our grades back after a day, which was really beneficial."
The school's head of maths, Jo Palmer, said it took a while to teach the girls which symbols to use, and how it would look.
"They struggled with ... which keys to enter x-squared or a square root," she said. "But the good thing was that it marked their work straight away and told them where they went wrong."
