The new GCSE system will free students from constant assessment and help them understanding subjects better, said the head of exam regulator Ofqual.
Glenys Stacey, Ofqual's chief regulator, told the BBC that focusing more on final exams means time can be "freed up so that students can actually learn and become competent in their subjects".
She added: "at the momnet too many students of whatever ability are sitting too many assessments".
The new numbers-based system for grading GCSEs will help less able students while making it easier to spot the most talented, said the head of the qualifications regulator Ofqual.
Glenys Stacey, Ofqual's chief regulator, said the move from eight gradings to nine means assessors "get a little bit more selection, which is particularly helpful at the top of the scale".
She told the BBC's Today programme that focusing more on final exams and less on modules would benefit the less able student, because "he's not going to be weighed down by assessment after assessment."
Ofqual said English literature, English language and maths will be the first subjects to undergo GCSE grade changes - these three subjects account for around a third of GCSEs awarded in England each year.
- The first three subjects to be revamped - English literature, English language and maths - are due to be taught in secondary schools in England from 2015, with the first exams taken in the summer of 2017.
- A year later, in 2016, new GCSEs in science, history, geography and some modern foreign languages, as well as other subjects often taught in schools like RE and art, will be introduced to schools.
- Ofqual will consult on the range of subjects that will carry the GCSE title in the future, a move which is likely to fuel speculation that some subjects may not be part of the brand.
The overhaul of the GCSE grading system will make it easier to spot the brightest students, Ofqual suggested.
Currently, in some subjects such as maths and science, high numbers of pupils achieve A* and A grades which makes it difficult to pick out the top students.
Chief regulator Glenys Stacey said that in these cases "you then begin to question whether the qualification is doing its job in differentiating sufficiently your most able students."
Traditional GCSE grades of A*-G are to be scrapped and replaced with a numbered scale under the biggest reforms of the exams for decades.
An additional grade will be added into the current eigh-grade system, with pupils to be graded from one to nine - with nine the highest mark available, England's exams regulator Ofqual said.
The existing GCSEs, which pupils have sat for nearly three decades, are to be swept aside, and a tougher and more rigorious exam will replace them, the Education Secretary announced today.
Pupils in England will attempt the new qualification from the summer of 2017. There will be less coursework and greater emphasis on final written tests.
Political Correspondent Libby Wiener reports:
As the government outlines changes to the GCSE system, we take a look at current maths exam papers. How well did you do?Read the full story ›
As the government outlines changes to the GCSE system, we take a look at current maths exam papers. How well would you do?Read the full story ›
Michael Barry, headteacher at St Matthews Academy in South East London has said that he is concerned that the changes to GCSEs "feel a bit rushed" and may be a knee-jerk reaction to the English GCSE fiasco last year: