Ministers are considering giving state schools the freedom to bypass GCSEs and fast-track bright pupils straight to A-levels, The TES has learnt.
New performance measures are also proposed, including an "advanced Bac" GCSE benchmark - building on the controversial English Baccalaureate (EBac) - and an "accelerated Bac" to reward schools that skip GCSEs.
"We are considering much greater freedom for schools to accelerate bright kids past GCSE to do either A levels or pre-Us and introducing league table measures that capture that and reward schools for it, not penalise them," a source close to education secretary Michael Gove said.
The source points to Singapore where they say around a fifth of pupils take A-levels without any intermediate national exams.
Ministers are concerned that schools in England that did the same thing and put 16-year-olds in for more advanced exams, instead of GCSEs, would be punished in the current league tables.
As a result they are planning an "accelerated Bac" for the GCSE tables to reflect and reward passes in "much harder" qualifications.
Changes to the data measures used by Ofsted would also be introduced for the same reason.
Brian Lightman, Association of School and College Leaders general secretary, said: "This would have to be thought out very carefully because at the moment GCSEs are considered for university entrance and by employers.
"Bypassing GCSEs would lead to a curriculum that was either extremely demanding or very narrow."
Some state secondaries in England already have under-16s studying for AS- levels but must still also enter them for GCSEs at some point.
The government source said: "We want a league table system that doesn't disincentivise schools from doing what they think is in the best interests of the kid.
"If, for example, you said a group of pupils in the top set in maths were going to skip GCSE and go straight to AS-level then we want to make it clear that they have done a great job. At the moment they would all score zero."
Ministers accept that the EBac would act as a "perverse incentive" in this respect. A campaign to abolish the measure - which requires at least C- grade GCSEs or IGCSEs in English, two sciences, maths, history or geography and a language - is growing among heads, who claim it is too narrow.
But Mr Gove says he "loves" the measure and ministers are now understood to be "very interested" in an even tougher GCSE benchmark.
The "advanced Bac" would also require at least grade C in English literature and triple science.
There are no immediate plans to formally include the measure in league tables but all the information needed to compile it should be publicly available by 2012.
It is also understood that the Government will carefully examine schools' performance on the "advanced Bac".
Sources say increasing the number and variety of measures schools are judged on reduces the opportunity for them to "game" the system.
But Mr Lightman said: "Turning different arbitrary collections of GCSE results into performance indicators is not a coherent way of developing the curriculum."
Dennis Richards, head of St Aidan's CofE High School in Harrogate, supports the EBac but said the idea of early AS-levels is "ghastly".
"To hothouse pupils in this way would be a matter for deep regret," he said. "Girls aged 14 and 15 already have increased rates of eating disorders because they are under so much pressure.
"It is also needless - the GCSE has been a fantastic success story."
Original headline: Ministers' plan for elite: forget GCSE and go straight to A-level