This is why I would hate being a teacher in England. I teach years 6 to 9 in France (in a collège). Most teachers wear jeans, only the head and deputy wear suits. I often wear knee high DMs and short skirts. I have tattoos and piercings. I sometimes dye my hair bright red.
When my Head started at our school three years ago, he did have a talk with me about toning down my appearance. I told him to stop worrying about it and focus on what was going on in the classrooms.
Since then I've become one of his favourites. I have no trouble with discipline, my pupils get excellent results and he gets good feedback from the parents about me.
Last year I had a 14 year old come up to me and ask for advice about getting a tattoo done. I told him to talk to his parents about it, and that he should chose a design, wait a year and see if he still liked it as much. I saw his mum recently, she thanked me because he had listened, and decided after about 6 months that he didn't really want that particular picture on his skin forever (he's chosen another one, and is apparently going to wait a year again, at this rate he'll probably never get a tattoo).
We actually have a relatively strict dress code by French standards. No spaghetti straps, no flip flops, no underwear on show, no leggings without anything over them, no micro shorts. Also school bags have to be rucksacks (two straps). It's applies to both pupils and teachers (well, apart from the bags).
Quite a few children have piercings, dyed hair etc. but they stick to the dress code so that's fine.
I quite often come across adults in serious, responsible jobs, who have tattoos, piercings, unusual hair and cloths. It's socially acceptable. So much for the English being tolerant.