The exam boards have been asked to develop new ways of assessing Britain's brightest teenagers. This follows ministers' decision last year to introduce "world-class tests" for nine, 13 and 18-year-olds.
Officials at the Qualifications and Curriculum Authority, who are responsible for the tests, hope to move away from traditional assessment. Every subject may be assessed in a different way as the QCA would like to develop exams which are tailored to suit each one.
Proposals include scientific investigations, pre-releasing exams to students so they have time to prepare and taking exams using computers.
The QCA has told boards that the tests must not require extra teaching and their assessment should not interfere with students' A-level studies.
A QCA spokesman said: "This is a new exam so there is an opportunity to look at alternative means of assessment.
"We also want to find the means that best suits each subject. Students will already be tested by traditional exams at A-level; the whole point of the advanced extension award is that it tests sudents beyond what is normally tested."
Five assessment methods will be trialled in May by around 1,000 sixth-formers in 90 schools and colleges who will test sample questions.
The new exams - officially called advanced extension awards - aim to stretch the top 10 per cent of students and enable universities to choose between pupils with equally good grades.
The tests, proposed last year as a surprise addition to a package of A-level reforms, were extended to include all major "academic" subjects after previous plans to limit them to six were condemned by heads.
They will piloted in five subjects next year - English, maths, geography, chemistry and French - and will be available from 2002 along with tests in biology, economics, history, German, Latin, physics, RE and Spanish.
Plans to develop tests in critical thinking were put on hold by ministers last year. The QCA has now recommended that this go ahead, but officials are waiting for ministerial approval.
Ministers are determined that the new extension level will remain essentially academic in nature and believe that its role in selecting candidates for leading universities could be undermined by including vocational subjects such as business studies.