A classic scam pulled off by a number of schools where you pay to wear your own clothes.
There seemed to be a theme in the past to each non uniform day - of which there were a lot - however now it seems to have been reduced to once a term with the only theme being “NO BUMS NO BOOBS NO BELLIES” (© Copyright Mrs Bowdler).
The most worn outfit is just a classic jeans and hoodie - much to Mrs Wharmby's dismay.