'Gender' on school policies

[JellySlice]

When I first checked, a couple of years ago, our secondary school used the correct language for the protected characteristics, though gender and sex were used interchangeably in the actual documents. Just checked again, and sex has disappeared and it's not gender all the way through. TBH I'm surprised, as they seem to be very common sense about how they treat the children who declare themselves gender-diverse.

Our LA lists the protected characteristics correctly.

Please guide me how to write to the school. I do not want to risk jeopardising my relationship with them, as I have two children there who need and get extra support and consideration.

You are perhaps overthinking it and worrying about their reaction in advance. Just take all emotion out of it, and write a calm and purely factual letter, stating that the protected characteristic is sex, not gender. Perhaps explain that this protects girls from having male bodies in their single sex spaces, whereas “gender” does not. And point out that they are required to comply with the law, as stated in the act.
You could add that you are sure they are not deliberately flouting the legislation, but you would appreciate them correcting their documents in line with the LA ones.

I adapted the 'lea guidance for schools' template here: safeschoolsallianceuk.net/resources-2/letter-templates/
Haven't had a response from the school though!