Putting pen to paper in exams should be scrapped in favour of using computers, the qualifications watchdog says.
Isabel Nisbet, outgoing chief executive of Ofqual, said retaining traditional writing materials would render GCSEs and A-levels "invalid" as "techno savvy" pupils were not used to using them.
She has now called for the traditional method of testing to be brought to an end, insisting the reliance on hand-written papers "cannot go on".
Writing in The Times Educational Supplement, she voiced fears that students could take only "bits" of a "very small" number of their A-levels and GCSEs on computers.
"They use IT as their natural medium for identifying and exploring new issues and deepening their knowledge," she said.
"Yet we are even now accrediting new GCSEs, due to run for several years, which are still taken largely on paper.
"This cannot go on. Our school exams are running the risk of becoming invalid as their medium of pen and ink increasingly differs from the way in which youngsters learn," Nisbet said.
If school exams fail to go online soon, exam preparation will become a "separate thing to learning", she warned.
Currently few sections of existing exams can be taken on computers but hand-written scripts are often scanned and marked on-line.
Andrew Hall, chief executive of exam board AQA, welcomed the remarks.
“It's really important that students are assessed in the same way that they learn and using the technologies that are commonplace in the world outside the classroom,” he said.
“The real prize here is to have assessment, online, on-demand, when the student is ready.
“This should also provide much speedier feedback to students and teachers, so they can identify areas of strength and weakness.
“It's crucial that we all work together to ensure equality of opportunity as this technology is rolled out, so that it doesn't disadvantage any student,” Hall said.
AQA has been offering on-screen exams for five years.