The first A* students at A-level will be "stretched to their limits" by the return of dissertation-style essays and creative writing in 2010, the WJEC exam board has said.
Analysis of the new specifications for English and history revealed that open-ended essay questions would put students' originality and initiative to the test.
Coursework would also be vital in singling out the highest achievers, although subject officers stressed that it should be completed in lessons - not at home, where students could get parental help or plagiarise.
Under the new syllabus, only candidates achieving 90 per cent or more would be awarded A*s.
The idea is to reward exceptional performers, following criticism that too many students are getting As.
WJEC figures show pupils who got near-perfect scores last year could share the same grade as peers who achieved 20 per cent fewer marks.
A* grades have already been introduced at GCSE, but will not be awarded at AS-level.
As part of the new syllabus, history candidates would write a 3,000-4,000- word dissertation-style essay. In the two-and-a-half-hour exam, they would be required to write three open-ended essay questions.
The new English language and literature A and AS-levels would give students a chance to write more creatively, with more focus on comparison and analysis of texts. They would also have to produce a coursework folder of 3,000-words, accounting for 40 per cent of the final marks.
A typical exam question could ask students to compare how language is used to establish power in relationships in Shakespeare's King Lear and Harold Pinter's The Homecoming.
Many classic texts remain on the syllabus - a Shakespeare play, Charlotte Bronte and Charles Dickens, for example. But a modern twist in English language would allow students to examine stand-up comics' scripts, phone- ins or sporting commentaries.
The best candidates would be marked out by their ability to think around a subject, WJEC officers told TES Cymru.
According to English officer Cerys Preece, the A* student would not necessarily be marked down on poor grammar, spelling or punctuation. But their ability to analyse and make connections in texts would set them apart.
Phil Star, history officer, said a return to an essay-writing format would help ease students' transition to university. "The essays really will close the gap between A-level and university," he said. "We are returning to the old-style essay, but this goes further and will really stretch the most talented young historians."
The new syllabuses address criticisms made by Tim Birkhead, professor of behavioural ecology at the University of Sheffield, in TES Cymru last week. He argued that too few undergraduates were independent thinkers. They had to be told what to do at every stage - a trait he put down to a "spoon-feeding and teaching-to-the-test culture".
Gareth Pierce, the exam board's chief executive, said: "WJEC welcomes the new A*, which will recognise exceptional performance by students who will be challenged to the limits of their capacity."