If teachers were asked what an average grade was in the new GCSEs, what would the answer be? Is it a standard pass - a 4 - or a good pass - a 5?

Or is it potentially any score from 3 - a near miss - to 7 - an approximate grade B in old money? The answer, I guess, depends on expectations and on context. But there is no doubt that thanks to the overhaul of GCSEs, and the addition of more granular grading, our understanding of average has been officially stretched.

I’d like to go further. I’d like to stretch “average” so far that we only use it sparingly and recognise that as far as individual assessment is concerned, it’s practically useless.

I accept that when teachers want to determine how a student’s abilities compare to his or her classmates or plot them against a national benchmark, “average” is a useful word. Everyone understands it. It’s convenient statistical shorthand. But it tells us nothing about a student’s problems and potential and even at the group level, as statistical shorthand, it obscures an awful lot.

Consider the following: the vast majority of students - 80 per cent according to our study of over 24,000 children - exhibit some type of verbal, quantitative or spatial ability bias. Even if the quarter of children at the top and the quarter at the bottom of the ability range are excluded, the remaining 50 per cent who lie in the “broad middle” show distinct differences.

Three-fifths of these “broad middle” children have a measurable propensity for or deficit in verbal, quantitative or spatial abilities (spatially able children think in pictures first before converting them into words). This means that although they might be regarded as solidly average by a school, they have very different learning strengths and areas for development.

This has a significant impact on outcomes at GCSE.

Among the half of students in the middle of the ability range, the chances of getting a B or above in English at GCSE ranged from one in 10 to seven in 10 in 2016, depending on their verbal ability bias.

This is because, according to our analysis, only 20 per cent of students who were weaker verbally gained an A or A* at English GCSE compared to 33 per cent who were more verbally able. Similarly, only 9 per cent of those “average” students with weak verbal skills achieved a B at GCSE English, compared to 38 per cent of those with stronger verbal reasoning abilities.

At the other end of the scale, over half (53 per cent) of students who were verbally weaker failed to gain a standard pass (or a 4 in new money) at GCSE English in 2016 compared to less than one in ten (8 per cent) who were verbally stronger.

Remember this is the “broad middle” of students we are talking about, not those at the top or bottom of the ability range.

If significant numbers of “average” students achieved so disparately last year at GCSE, what use is the word as a teaching aid? It won’t help teachers identify struggling students or those who with a bit more support could really motor.

Let’s look at the issue from the student’s perspective. What does the word “average” do for them? Does it inspire? Does it instil confidence? Does it encourage?

There is a reason parents refrain from calling their children “average”. “Our Evie is so average,” is not a boast often encountered at the school gates.

It doesn’t do justice to the array of abilities, talents and problems that make up an individual. “Average” blurs distinctions; it masks personalities.

Schools should emulate parents. They shouldn’t let those three syllables define so many students. It suggests that any problem cannot be serious enough to worry about and that any potential is too feeble to shine. That’s not fair and it’s not smart.

At a time when new GCSE grades have stretched the “middle”, when rigid setting has been called into question by new research from the UCL Institute of Education, isn’t it time that we accepted that every child is basically in a set of one? We need a more fluid approach to assessment and we shouldn’t put teachers in the invidious position of making broad judgements based on crude data. We could start by refusing to call any child “average”.

Shane Rae is head of publishing at GL Assessment

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