Impact: The Hydra of Education

I have been working with a lot of my client schools of late on the impact paradigm in education - and how, in our rush always to see the impact of what we do through a narrow and sometimes exclusionary metric, over a short and finite timeframe, we are blinkered, and problematically so.

It seems to me that there is so much impact - positive and negative - which does not show itself when we want it to, where we want it to, how we want it to - and yet, even though we know in our gut this to be true, we continue to chase it within those narrow confines, and, worse, castigate ourselves and our students, or, even worse, allow our students to castigate themselves and their parents to compound this, when the confines prove too narrow.

But when I found myself blaming Hattie for his role in propagating and perpetuating the myth of confined impact, I thought I would listen, intentionally, to what he is actually saying. Rather than, as so many have done with Dweck and Maslow and the like, simply allowing what people are always saying about what he is saying somehow to morph into his voice, when it is not.

And so I listened, recently, to an episode of the Talking Teaching podcast from the Faculty of Education at the University of Melbourne, on which, in July 2025, reflecting on his extraordinary career, he helps me bust a few Hattie Myths. And here are some snippets that stuck with me.

“We should be looking for evidence that we are wrong”: he speaks about this wise counsel from Carl Papa, which actually spearheaded much of his own work. He explains, “Why is it every teacher can tell you what they do works? Why is it every government tells you their policies work? Why is it every article says it works? Why do we have a profession that says everything works?” And he seeks to reframe this from “What works?” to “What works best?”, using that as a conduit to focusing on the conditions. And I breathed a sigh of relief.

“It soon became obvious that people were misinterpreting what I was trying to say.” In other words, educators were leaping to the league tables of impact measures, and using them reductively. He says, “I’ve spent the last 15 years trying to get the message out there that it is about the underlying things, not just the methods themselves”.

Or, in other words, the impact measures were just probability. The truth lay within the conditions; the context. He cites a colleague, Alison Jones from the University of Auckland, who said to him once “I’m stunned that you know classrooms to the second decimal point.” And this pushed him even further towards trying to understand the real game changer, “the social psychology of classrooms”, seen, as he says, “through the eyes of the learner”.

He says the real questions are these:

1. “To what degree are schools inviting places for students to come to?”
2. “Do students feel like they belong in this place called learning?”

Yes! Hattie, like me, is a big believer in belonging as a foundational priority for schools; and not as an alternative to academic achievement, but as a contributor to it. And then he says something which encapsulates so much of what I say when Secondary schools argue they have to focus on narrow, academic metrics, because that’s what matters to universities: “We are not a selection mechanism towards tertiary. Those days I would have hoped would have gone, but they haven’t.”

Persistence and Fadeout Dynamics

This paper explains the significance of persistence and fadeout in the impacts of child and adolescent interventions. In other words, impact can disappear, but it can also persist - and this is true of impact that is demonstrably positive as well as that which is inarguably negative.

Unexpected Long Vortices

How might affinities, practices, or knowledges nurtured today create deep, disruptive currents 30 or 50 years later? Whilst most recent in our minds is the example of the COVID pandemic, this paper details the long-term effects of unexpected interruptions in compulsory schooling, through the example of storm-ridden regions in India. So, in fact, and existentially so, we needs must design for generative resilience, not just immediate performance.

Epistemic Ripples

What emerges when you treat impact not just as what we intend but as how knowing shifts over generations and geographies—like soil bearing unseen seeds? This is what I found myself reflecting upon when I read about the extraordinary example of the amazing “Cottage by the Sea” project. A counter narrative to the long-term impact of trauma - something of which my own body has definitely kept the score - this argues that impact is about cultural transmission as much as individual knowing.

Effects and side effects

And finally, Yong Zhao's paper, “Effects and Side Effects: What Is Missing in Education Research”, calls for a fuller accounting of educational consequences. Much like my own work on ‘The Wellbeing Footprint’ does too, about which I am honoured to have written another article, for ISC Research.

Thinking recently of the importance of ‘upstream thinking’ when we design for wellbeing and belonging (and for everything else, really) set me thinking about downstream thinking too, which got me to thinking about both, simultaneously: ‘thinking midstream’, if you like. (If you’d like to play ‘upstream’, there are much worse places to start than with Tricia Friedman.)

So, please, let’s start to think differently about impact in education: it is our Hydra, a creature of many heads. Sure, sometimes it appears quickly, nearby and in ways we would have hoped, or it appears equally swiftly and proximally, even in ways we never intended. But oftentimes it doesn’t. And the important thing to remember is that, if it doesn’t, that doesn’t mean we haven’t made students’ life and learning better, but nor does it mean we have actually managed to follow the silent code we all took as educators: namely, to ‘Do No Harm’.

By Matthew Savage