Ofsted is "concerned" that its inspectors are still looking for detailed marking when judging schools – despite pleas for them to steer away from the practice.
Sean Harford, national director of education at the inspectorate, has called on inspectors not to make judgements, or recommendations for improvement, on marking practice.
But in a message to Ofsted inspectors yesterday, he wrote: "I remain concerned that we continue to see some inspection reporting which gives the impression that more detailed or more elaborate marking is required, or indeed that it is effective in promoting pupils’ achievement.
"Inspectors must not give the impression that marking needs to be undertaken in any particular format and to any particular degree of sophistication or detail."
Two years ago, Ofsted clarified in a “myth-busting” document that it does not require “any specific frequency, type or volume of marking and feedback”.
And in the past three Ofsted updates, it has highlighted the recommendations of the workload review groups on marking, planning and data management. But it says that the "myth" around detailed marking remains.
In his letter, Mr Harford says: "Marking has proved to be one of the harder myths to bust. In part, this has been because we have continued to report on it extensively at some inspections, especially with reference to areas for improvement in previous inspection reports from some time ago."
'Little evidence to support extensive marking'
Earlier this year, the government-commissioned review group looking into workload found there was “little robust evidence” to support the use of extensive written comments when marking pupils’ work.
And in April, the Education Endowment Foundation found that there is hardly any evidence to suggest that detailed or extensive marking has any significant impact on pupils’ learning.
Following these findings, Mr Harford said: "Please do not report on marking practice, or make judgements on it, other than whether it follows the school’s assessment policy.
"Also, please do not seek to attribute the degree of progress that pupils have made to marking that you consider to be either effective or ineffective.
"When reporting, please do not make recommendations for improvement that involve marking, other than when the school’s marking/assessment policy is not being followed by a substantial proportion of teachers; this will then be an issue for the leadership and management to resolve."
Kevin Courtney, general secretary of teachers' union the NUT, said: “Too many headteachers are not taking Ofsted seriously. Heads tell you they are worried a particular Ofsted team might not follow the Ofsted official line. And you can see that argument: Ofsted teams are variable and the consequences of failure are severe."
But he added: "Heads have to be braver. They have a responsibility to their staff and to their pupils to manage teacher workload – and to stand up to poor Ofsted teams.
“Teachers also need to challenge their SLT if marking policy and other workload areas don’t change. Teachers can approach this collectively and rely on the support of the NUT in reducing their workload.”
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