Michael Gove today raised the possibility of limiting the number of students that achieve top A-level grades.
The Education Secretary also suggested teenagers could be ranked on their results.
Speaking at a conference on standards arranged by exams watchdog Ofqual in central London, Mr Gove said he wanted to "open up the debate" around changing the A-level system.
He suggested that in the future, only a certain fixed percentage of students could be awarded an A* at A-level.
This system, known as "norm referencing" was used to grade exams between 1963 and 1987.
Under the current system any student that gains an A overall as well as scoring at least 90% in each of their papers in the second year achieves an A*.
Mr Gove told the conference "we can't go back to a situation where all exams are graded on the basis of norm referencing."
But he said: "I think it's important to open the debate.
"Could it be the case that while we award As, Bs and Cs entirely on the basis of criterion reached, is there a case for exploring whether or not A*s should be allocated only to a fixed percentage of candidates.
"I would like to see that debate explored and engaged with."
Mr Gove said: "There's another question as well - should we publish more data about how all candidates perform?"
He suggested that alongside pupils' final A-level grades more information could be produced so it is known "how they are ranked depending on the subject".
This could mean national rankings which would show the top students in the country in each subject, and allow teenagers to compare their performance with their peers.