The NASUWT has always opposed the practice in some schools of grading the outcomes of lesson observations.

It is well established that observation grades cannot be awarded on a valid or reliable basis and should not, therefore, be used to form judgements about the performance of individual teachers, particularly in the context of schools’ performance management arrangements.

In light of the serious limitations of grading individual lessons, Ofsted discontinued the use of lesson grades in school inspections in 2014.

While this decision contributed to a decline in the prevalence of this practice in schools, the NASUWT is aware that observation grades continue to be used in some instances.

It is, therefore important to ensure that, where necessary, schools and employers are made aware that it is the clear view of Ofsted that grading individual lessons is an inappropriate means of forming judgements about the performance of individual teachers.

In its current school inspection handbook, Ofsted confirms that it does not require schools to use the Ofsted evaluation schedule to grade teaching or individual lessons.