Don't use Mock Exams as a basis for CAGs as it is essentially the real A levels (which were cancelled) but much sooner. Teachers should be advised to use evidence to create a case for the grades given, such as topic tests from Year 1/2 as well past predicted grades and UCAS predictions.
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Most students achieve much higher in the final exam and some students have sat their mocks before the cancellation. This is much worse for students as their mental health will plummet. With the disruptions from the pandemic having mock exams is just as unfair as the real exams. Most schools have announced that they are using these mocks as the basis of their CAGs.