Why mark out of 8?

Education Secretary Michael Gove wants to scrap the existing A*-to-G GCSE grading system in favour of a numerical marking scale from one to eight, with eight being the top score. So why mark out of eight?

First of all, it must be noted that GCSEs are already marked out of eight. A*,A,B,C,D,E,F,G. That adds up to eight.

The similarity between the old system and new has been noted by Rob Hague on Twitter.

"Suggested question for Gove's new Maths GCSE: "Explain 'isomorphism', with reference to the numbers 1-8 and the set {A*,A,B,C,D,E,F,U}."

GCSEs didn't start off this way - 7 grades were originally sufficient to separate out the wheat from the chaff.

It became increasingly difficult to separate out the wheat from the very good wheat and the A* was introduced in 1994.

Since then, it has become increasingly difficult to separate out the very good wheat from the really, really excellent wheat.

From 1994 to 2012 the percent of GCSE marks at A* went from 2.8% to 7.3% according to grade analyst Brian Stubbs.

But introducing an A** would risk some people's CVs having more asterisks than a payday loan advert.

Turning grades into numbers does make it easier to introduce a new top mark if needs be. If it's 1-8 you can always roll out 9 or even 10.

"Does this allow for 9 & 10 when they get too easy?" tweets Nigel Buckton.

If you started with 10, and grade inflation meant you needed an 11, it would all start to look a little bit Spinal Tap.

The government won't concede that Nigel Tufnel is the inspiration for the current regrade.

The regulator of qualifications, examinations and assessments, Ofqual, says it is to avoid unfair comparison between GCSE grades and the new system as they won't correspond with each other.

But if they are trying to distance the new system from the old, keeping eight grades is curious.

It's a comparatively high number of grades.

British undergraduate degrees have five classifications: First-class honours, upper second-class honours, lower second-class honours [aka a "Desmond"], third-class honours and then an ordinary degree.

Music grades have three: Distinction, merit and pass.

It's even less for the driving test. You can either pass or fail. Even the Stig probably didn't get a distinction.

You can follow the Magazine on Twitter and on Facebook