I’m always on the hunt for effective ways of representing the many and varied components of, and influences on, education. To include everything makes for an over-elaborate image, although the busyness faithfully reflects the complexity of the thing. Simplifying the model makes it easier to identify egregious influences, but risks over-simplifying the picture.

One approach might be to think of education as a journey, with schools as the vehicles in which the journey is made.

In this automotive analogy, pedagogy - the teaching and learning nexus - is the driver. Ideally, we should be thinking in terms of a car fitted with dual controls, the student driving, the teacher sitting alongside, guiding but with feet covering the second set of pedals. Curriculum content might be characterised as the fuel. Technology might, albeit ambitiously, be seen as the accelerator, insofar as the proliferation of platforms and devices, social media, and prospective developments in artificial intelligence, virtual and augmented reality, promise to re-write the rules of educational engagement.

Digital developments might conceivably free us from the current constraints of period (the rigidities of the timetable and the school day), place (the physical confines of the classroom), path (the teacher’s toolkit) and pace (the tempo of the class and the progress of individuals within it). Truly an accelerator.

The clutch and gearbox bring to mind the teacher’s ability to change to accommodate the different speeds required for individual students - differentiation.

There are two “external” factors that seem to slow progress. One is the condition of the educational estate, and this may be likened to the make and model of the vehicle itself. Given that many teachers teach, and students learn, in classrooms and buildings that were designed for a very different educational purpose, it’s as if we were attempting the journey in an educational Escort, or a curriculum Cortina. Two of the three Rs might well turn out to be Reliant and Robin.

Of course the vehicle requires a brake. Teachers are skilled at using it to respond to student development along the journey, slowing down where necessary to consolidate and re-group. But some of the external influences might better be characterised in terms of the handbrake on a car.

Here we come up against the prevailing public exam system. The drag created by unnecessary public exams at age 16, in particular, and the use of such outcomes as an accountability measure, makes it seem as if we’re trying to drive at speed with the handbrake still on.

Even more worryingly, the exam regime seems to dictate the route, if not the destination. As educators, we think we know what we want to reach - the development of rounded, self-aware, confident and critical individuals, ready to take their place in society, delivered through a broad and balanced curriculum.

The question is whether the exam system acts as a brake, in which case it “simply” slows us down, or as an erroneous entry into the car’s satnav, in which case we are in danger of going seriously off course.

Kevin Stannard is director of innovation and learning at the Girls’ Day School Trust. He tweets @KevinStannard1