I like my DC to wear sunglasses outside when it's very sunny, as it has been the past couple of days, to protect them from UV rays.
DD (6) tells me I have to send in a letter to say I want her to wear her sunglasses, otherwise she's not allowed to wear them (no problem, I can write a letter, and will say why I want her to wear them, as well as a hat) just thought it was a bit odd).
A teacher friend tells me children at her school aren't allowed to wear sunglasses, but she didn't know why not. 
Just wondered what is normal.