It is a sin to observe other teachers’ lessons simply to tell them how to teach, according to one of education’s most influential researchers.

Professor John Hattie, director of the Melbourne Education Research Institute and one of the world’s most widely quoted education academics, told a conference today: “I think it’s a sin to go into a classroom and tell another teacher how to teach. Because all you do is tell them how to teach like you.”

He went on to say that 80 per cent of what happens in the classroom remains unseen and unheard by teachers - only the pupils are aware of it. “So why would I give a damn about reflective teaching?” he said. “I don’t want to think about the 20 per cent we see. I want to think about the 80 per cent that goes on that we don’t see.”

This, he says, is where testing comes in. The role of testing, he believes, is not to test pupils’ knowledge: it is to test whether teaching is effective.

“I should be learning something about what impact I had, who I had an impact on,” Professor Hattie said. “What I’ve taught well and what I haven’t taught well.

“Because tests don’t tell kids about how much they’ve learnt. Kids are very, very good at predicting how well they’ll do in a test.”

Professor Hattie was addressing hundreds of headteachers and academics at a conference in London today held to discuss his seminal work, Visible Learning.

During his keynote address, Professor Hattie insisted that, rather than telling one another how to teach, teachers needed to listen to each other. Just as pupils flourish in a culture where they are allowed to learn through mistakes, so do teachers.

“Foster that interdependence between staff, so it’s OK to say, ‘I’m struggling with these kids - can you help me?’” Professor Hattie said. “But I see staff sitting at the same table in the staffroom, working alone.

“It really is this notion of how you build this trust, both in the classroom and in the staffroom.”

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