Are any of them allowing shorts with this weather?
Our one was handing out two day exclusions last week to anyone who showed up in shorts and wouldn't/ couldn't go home and get changed.
I feel like in this day and age (but especially in this weather) tights are just so old fashioned. I myself have been living in cycle shorts and those sweat-wicking jogging leggings which are actually great for this heat, both of which are deemed too inappropriate by the school "because it shows the shape of the girls bum". But logically they're all out after school together with "the shape of their bum" in full view of the boys, so who exactly are they concerned about?
Idk maybe I can understand if they were the type you can shoot peas (and see pants) through, but why are we still so obsessed with what girls are wearing? And even if it is all about appropriateness and modesty, how are sheer tights and a mini-skirt better than practical joggers, sports leggings etc? I honestly think she'd look better / more modest in a pair of knee length jogger / board / cycle style shorts than the tights and "belt skirt" her and every one of her friends wear.
I remember back in school dreading this weather because I had mahoosive boobs, so I could either wear a size 14 tent that buttoned up but looked awful, or a size 8 that fit me but couldn't button up which meant I cooked all day in a jumper.
I feel like we should be pushing for a more European stance. Malta just recently switched out shirts and ties for tracksuits, for example. The primary school cares more about your child being in school (even if its pyjamas because your washing machine broke down or some other family emergency) while the high school is sending children home for the wrong colour of shoe laces. 
Emailed the school asking the logic behind the decision and got a total non-answer in reply, so I'd be interested to know how other parents feel and what other schools are doing (if anything).