Published on: 22 Sep 2017

What does ‘average’ actually mean?

Human beings don’t line up perfectly, there is no average learner. They all have their strengths and weaknesses. Even geniuses do.
Todd Rose, Harvard academic

In the 1950s the US Air Force realised that its planes’ cockpits were too small for its pilots, who had tended to put on pounds and inches in the 30 years since they were first designed for the average airman. So it commissioned a survey of 4,000 pilots to figure out what the new average was on a range of ten dimensions.

When the results were in, the air force was surprised to discover that not a single pilot was average across all ten fields. Even when the dimensions were reduced to three, only 3.5% of pilots registered as average in all of them. A pilot who was short in the leg could be long in the arm and vice versa. Varying chest circumferences, torso lengths and head sizes made any concept of average redundant.

Harvard academic Todd Rose recounts this anecdote in his book The End of Average, in which he argues that school systems often do what the USAF had tried to do: they prize standardisation and ignore variability and individuality. “Human beings don’t line up perfectly,” he says. “There is no average learner. They all have their strengths and weaknesses. Even geniuses do.”

If we take this into the classroom, what do you think an ‘average’ learner looks like? Or more specifically, what do you think is the typical ‘average’ grade in the new GCSEs? Is it a standard pass, a 4, or a good pass, a 5? Or is it potentially any score from a 3, a near miss, to a 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, though. 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 hides far more than it uncovers.

There are, of course, times when ‘average’ is a useful term – particularly when talking about trends in a class, across a year group, in a school or across a MAT or the country as a whole. But as our new report shows, the term ‘average’ can have distinct limitations for teachers and students. As teachers will only be too aware, two identical scores can hide startlingly different stories. Maybe it’s time we started to look more closely at the ‘lost middle’ and found more ways for them to shine.

Read GL Assessment’s new report, The Lost Middle, published today.

By Shane Rae, Head of Publishing, GL Assessment