Mary Myatt is a lead inspector for Ofsted, adviser, writer and trainer who blogs at She kindly agreed to write this blog for us after appearing at a panel at a joint Teach First & Teacher Development Trust event on Lesson Observation. You can see the vidoes here

If  there was any doubt about the inaccuracy of lesson observations, they were squarely squashed by Prof Robert Coe during the lesson observation debate organised by David Weston from the Teacher Development Trust and Sam Freedman from Teach First. It is not possible to judge accurately the quality of teaching from a twenty minutes lesson observation. So why are lessons graded?

To be clear, inspection teams make judgements on aspects of teaching, achievement, behaviour, leadership and management when they visit lessons. And they only make a note of evidence if they find it. But this evidence doesn’t stand alone. It is always, always backed up with further information. These include data on progress, talking with students, the views of students, staff and parents. So the commentary when feeding back to staff should be along the lines of ‘on the evidence of what I observed during the time I was in your lesson, these aspects were outstanding/good/require improvement because..’ It must be made clear that these are not judgements about an individual’s overall practice, but based on what was seen during the observation.

What goes wrong is when schools simply aggregate grades from the lessons observed and state that these equal the quality of teaching over all. This is highly misleading if it hasn’t been triangulated with some of the other measures.

In order to overcome the narrowness of lesson grades here are four suggestions for schools to create evidence which is robust, fair and does not rely on individual lesson observation grades.

One: Improving practice is based on Lesson Study models or on formative conversations involving everyone, including senior leaders on what works. Tom Sherrington has posted about the impact of Lesson Study and he notes the change in dynamics of working in this way. Talking about teaching is a top priority: Alex Quigley has posted about ‘creating a climate where quality teaching is the subject of conversations at all times’ where he draws on the Hattie research and links to a brilliant, short clip of Tim Brighouse describing how this works. Chris Moyse has also written about how his school does not grade lessons, but colleagues work collaboratively and formatively to improve practice.

Two: Carefully considered student perception surveys are in place. This was one of the most interesting things to come out of the the TDT/TF debate. There is an emerging body of research which shows that one of the most accurate indicators for the quality of teaching comes from students. It is possible to do this and get high quality responses where surveys are carefully constructed. So that there is no room for personal, irrelevant comments.

While a great deal of work was done on student voice several years ago by amongst others, Professors David Hargreaves and Jean Ruddock, it is now being replicated by the Measures of Effective Teaching project. If schools were prepared to trial some of these surveys, summarise the results and show how they were taking the key messages on board, it would provide another plank of evidence for securing a judgement on the quality of teaching.

Three: Video lessons are a part of practice. The more we do anything, the better we get at it. And that includes observing lessons. We need to be watching other people’s practice, ideally through lesson study type models and through watching videos of others teaching. There are plenty of examples. And by extension, it is a good idea for individuals to watch video footage of their own practice. John Tomsett has written a commentary on his videoed lesson. How would it be if there were a summary of samples of lessons which had been videoed? Again, it would create another solid basis for reaching a judgement.

Four: An ongoing professional interest into what the research is saying. These may be large or small scale, but they are considered, discussed and elements selected which are appropriate to the school’s context. Some of these might be the work done by the Education Endowment Foundation, Hattie’s Visible Learning the Teacher Development Trust’s National Teacher Enquiry Network. The concise summary for instance of an admittedly small-scale piece of research by Sam Freedman at Teach First on the difference between ‘strong’ and ‘exceptional’ leadership would provide substantial material for discussion on taking school improvements to the next level. If a school is carrying out this sort of practice, it will have an impact on teaching standards, not overnight, but over time. And it is worth capturing this, as brief headlines both for the satisfaction of seeing the journey and as evidence for an inspection.

The above should be triangulated with data on progress for all groups of students. And from this it is possible to reach a judgement about the quality of teaching in the school.

A brief summary including impact on the above should be included in the school’s SEF so that is highlighted for the inspection team. Time on inspections is very tight, so if there is a clear brief summary of practice and headline impact it is more likely to be picked up and acknowledged by the team.

None of this is a quick fix. It is about long standing practice encouraged and nurtured over time. And not a clipboard in sight. Schools working to these principles are likely to be on the road to good or better.

You can find out more about Lesson Study through TDT’s National Teacher Enquiry Network