jamsandwich - you are right about people not understanding anxiety. I have had some awful comments from people over the years. For example that I should just tell dd to pull herself together. If only it were that simple. We even had a SENCO tell us she was just stubborn and naughty.
On the plus side. In general the teachers we have had have been excellent once we have explained things to them properly. DD enjoys school has lots of friends and is very happy.
The getting to school early really does seem to make the morning calmer.
The most important thing to remind the teachers is not to make comments about not speaking. If the teacher boosts confidence in other areas the speech will slowly follow in many cases. Questions such as are you going to be good today and talk to me are not appropriate. Make sure all members of staff know this.
Making a child a helper is good. Asking them to get the register or fruit builds confidence.
Remind the teacher not to give up on asking questions just because they don't answer. They can still ask them to think about a particular thing.
Giving them gestures is helpful as well. When my dd taps the teacher on the shoulder twice this means she wants to go to the tiolet. We agreed this at the start of last year. This saved us from the accidents of the reception year. Now that she is gaining confidence speech is starting to follow.
DD still does show and tell even though she does not speak. She shows and the teacher asks questions that require a yes or no answer. In the beginning she just nodded or shook her head but now she actually answers
Lunch times can be a problem make sure you inform the dinnerladies of the situation. They will not know unless you inform them. DD now uses sign language to say thankyou. This saves her being told off for rudeness by staff.
If you are faced with anybody who implies you are just being silly and there is nothing wrong with your child hand them a leaflet and walk away.
BTW not preaching here just want to share what has helped us all so far.
asdx2 thanks for that tip may be useful for us in KS2.