Dr Stobie, speaking to the Herald ahead of his organisation's annual school conference in Singapore next week, said a major theme would be effective use of technology.
The Cambridge system is more examination-based than NCEA.
Dr Stobie said he was aware of the debate about the two systems' merits, and that many viewed Cambridge as more traditional. "I still think there is a place for some of the things that have come from the past, but I think, equally, the world is changing."
Exam booklets were already being scanned and marked electronically, but extending that to assessments posed challenges. He could not estimate when the change might happen. "We don't have the answers yet, but we are certainly taking the questions very seriously indeed ... at some point in the not-too-distant future, students will be sitting their assessments on a computer."
Issues with electronic assessment will also be worked through by Massey University, which is trialling a remote monitoring system.
Students will be watched by supervisors using a webcam and their typing patterns checked to guard against cheating. Staff will test the system this month, and if there are no technical glitches, a small number of summer school students will take voluntary, non-graded tests, with larger trials next year.
The Massey trial is being watched by NZQA. Its NCEA system involves two million pieces of paper moving around the country.
Keyboard is mightier than the pen
Trading the frantic scribble of exams for touch-typing would be welcomed by ACG Parnell College student Jonathan Edmeades.
"Definitely - it would be much better for your hand," said the 18-year-old, who is in his last year of school.
"More and more of what you have to do in the workplace is based around computers and being able to type fast and that sort of thing, so I think it would give you the skills necessary in a modern world."
However, he said any change would need to be matched by universities. "While most universities are still using paper and pen exams, I think you still need to know how to sit down and write an exam in three hours - you need to have that ability."
He thought using electronic devices for assessment would need to be carefully worked through.