Ofqual has said individual subject teachers could be asked to quantify the amount of learning loss their students have faced, which could be displayed alongside their qualification.
Speaking at a Commons Education Select Committee hearing this morning, interim chief regulator Dame Glenys Stacey said: "First of all, we have said to government…one way to recognise differential lost learning would be for the teacher in an individual subject to make some evaluation of that.
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"It would need to be kept quite straightforward, I think, in order to be doable, but you might be able to rate that in some way, RAG [a traffic light system of red, amber or green] rate it or something," she added.
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"Our point, though, is although that could sit alongside a qualification grade so the qualification grade could tell the users of that qualification not just next year but over an enduring period of time what knowledge and understanding of the subject that student has so that grade serves its purpose, and alongside it there could be another differential measure of lost learning."
However, Dame Glenys added that some students might want this information separately rather than displayed beside their qualifications.
“And also I do think there’s a debate to be had about whether that is simply days lost to school because there will be students who’ve had few days lost but will have lost a mother to Covid, or will be looking after siblings because their mother is a key worker on shift,” she added.
“So there’s a question over whether more qualitative information could be displayed in some way.
"The reason why we don't say that plays into the grade is that the grade and the marks that underpin it have a purpose – they are to show the knowledge and understanding of the subject and, indeed, qualifications by statute need to do that.
"If we were to try and import that into the grading, I think it would distort and confuse what the grade is about," she added.
Last week, Tes reported that the expert advisory group into differential learning loss could recommend that students be given a Covid "asterisk" alongside their 2021 exam grades to denote learning loss, to help them progress on to higher or further education.
In the meeting, Dame Glenys also said that teachers should not gather portfolios of student work as a basis for teacher assessment in 2021.
Dame Glenys said the idea of this "worries me greatly and I do hear from schools that teachers, until they have certainty, have been doing this, and I would encourage them not to".