NotSpaghetti
MrsNemo and others... the cat story is a total fake - though Suella Braverman fell for it!

The transcript of the conversation clearly shows that the girls were told - by a teacher - that believing that another pupil is not a cat but a girl is 'despicable', and that they are not welcome in the school with that attitude, so whether or not they were speaking hypothetically is irrelevant, really.
So - not a 'total fake' at all, but a possible misunderstanding, as it is not clear whether the catchild in question is real or hypothetical. The Head denies that anyone actually 'presents as' a cat in class, but saying that is in the interests of the school (and potentially of the catchild), isn't it? The fact remains that the school's ethos is one where speaking the evidence of one's eyes (ie saying that a child is not a cat) is to attract censure, which is the point - we have definitely fallen through the looking glass.