When the news broke a few months back that Ofsted was no longer going to grade the quality of teaching in individual lessons, the sound of coffee mugs clinking in celebration could be heard in staffrooms up and down the country. This jubilation was for two reasons, one practical, the other philosophical.

On the practical side, the decision removed a sliver of fear. No teacher wanted to let their school down or give a lesson that was judged to require improvement or be inadequate. Nor did they want to be identified as a disappointment by the headteacher - and they weren’t fooled by assurances that Ofsted grades had nothing to do with performance management.

And, philosophically, the vast majority of teachers felt it was wrong to judge the quality of someone’s teaching on the basis of a 20-minute observation. What if the dog had been sick on the mark book that morning? What if Tamara had chosen that lesson to let the world know why she hated school? Snap judgements were surely not fair.

But before the celebratory coffee goes to your head, it is worth remembering that inspectors are still making judgements on behaviour and achievement in every lesson. And Ofsted judgements still fall like rows of dominoes. If an inspector decides that the behaviour and achievement in a class are inadequate because the kids are swinging from the curtains, the implication is that the teaching is not sufficiently engaging.

So how do inspectors arrive at a judgement on the overall quality of teaching under the new arrangements? And how should school leaders and teachers prepare?

Same difference

Ofsted will be piecing together a picture of teaching not in a single lesson but over time - and inspectors will be extrapolating from the moments that they do see. If students arrive promptly for a class, settle quickly and immediately start work on the starter activity, inspectors will conclude that this is probably typical. Such behaviour is a result of consistent high-quality teaching: good learning habits become ingrained over many weeks.

Inspectors also talk to students in lessons. They ask about target grades and what the student has to do to make progress. They know very well that the class is likely to be on its best behaviour with them in the room, so they ask if current behaviour is typical. Similarly, they are not fooled by a whizzy lesson - they simply enquire whether this is the usual style of teaching.

Exercise books are another valuable source of evidence. What does the presentation say about the teacher’s expectations? Has the book been regularly marked? Is there evidence that the student has responded to the teacher’s comments? Most importantly, is the work challenging and is there evidence of progression?

Question time

As a teacher or a school leader, inspection is all about telling your own story, so steer the narrative rather than passively responding to the picture that inspectors are forming. They will consider any evidence that you put in front of them. It’s no use slumping in the staffroom after the lesson, bemoaning the fact that they did not see the wonderful work you have in online portfolios. If the exercise books look scrappy because most of the good work is stored in folders in the cupboard, then get those folders out. If you teach a practical subject and have just started a new project, ensure that displays of previous work, or at least photographs, are to hand.

Parents’ comments shine a light on teaching, too. Don’t just rely on the responses to the Ofsted questionnaire; present your own surveys of parents’ and students’ views to the inspectors, alongside any other student voice feedback you have.

Senior leaders carry out joint observations with inspectors and the headteacher is present at all meetings as inspectors crystallise their judgements. If you feel that a lesson has been unrepresentative, present your case. Most inspection teams will respond sympathetically if leaders feel that the best teachers have not been seen, and will observe lessons as requested. This can, of course, backfire spectacularly if the lessons turn out to be poor.

Individual grading may be no more but that is no reason to assume that lessons don’t count in inspections. They play as much of a key role as they ever did. As a teacher, you need to ensure that your lesson is fantastic, not by delivering a showstopper that you’ve created because you are being observed but by demonstrating good teaching over time. This is what enables students to make progress - and we can all celebrate that.

Roger Pope is principal of Kingsbridge Community College in Devon