I remember having heat stroke at school because I was forced to wear my uniform, which was like normal English uniform except that I was forced to wear a blazer and if I didn't I'd get detention every day until I wore it.
Our school systems are a joke when it comes to uniforms, I'm all for uniforms, but every school I've ever been to as a kid never had a Summer or Winter uniform schedule, it was just always black shoes, trousers, white shirt, tie and blazer.
It doesn't help that the black always drew in the heat, but that didn't make a difference, even when teachers could just wear shirts when ever they wanted and female teachers came in summer dresses. It's a fucking joke.
EDIT: Seriously, people complaining saying "That's not hot" is ridiculous. If you weren't born in this country and grew up to It's climate, you wouldn't understand what we think is hot. Everyone isn't born feeling the same climate in every country.