Private Schools and the Uniform Code

I, as a private school student through my entire academic career, fancy myself a bit of an expert on uniforms and dress codes.

First the punk/goth look doesn't fly. Don't believe me? Many schools have rules regarding hair, make-up, jewelry, footwear, and even gum chewing.

My old school handbook has this to say on the question

Hair:
Hair, for girls, may be colored, permed, or .otherwise treated. Unnatural tones and styles may not be worn. For boys, hair may not touch the raised shirt collar, may not cover the eyes and must not be treated with unnatural colors and styles.

Accessories:
Rings, bracelets, and necklaces may not be worn unless in association or according to ones medical needs or religious convictions. earrings may be worn but may be no larger than a nickel. For females, nails may only be painted in nude or skin tones. Males may not wear nail polish of any kind. Small amounts of face powder and blush are permitted, however, all make-up applied will match the skins natural tone.

Shoes:
Shoes most be worn at all times and must be closed-toe, black, soft-soled with Velcro or laces. Students changing for gym will also require...

...And so on and so forth. .

While we have been given indications that Hogwarts is more lenient than this particular private (thats night, private, not Catholic) school, we have never been given any indication that they would allow students to come to class in short and revealing tops with their hems still smoking from severing spells.