Does this seem crazy to you? I appreciate they have strict uniform rules, and I also completely understand that DD should know the rules by now, she's 14.
However, she has been wearing these shoes for 3 months, they are black, as the school requests, but not leather, more of a canvas type. Why not just tell her that she must not be seen in them again, rather than sending her home to change them mid-morning.
She is adamant this hasn't been mentioned before - I was wondering if it was a last straw type approach but apparently not. She has missed maths, which she is struggling at, moved down from top set a few months ago and is keen to get back in it.