N.,
My oldest son has Asperger's and he does not like change, all he knows is he is from "Misawa, Japan", he does not remember the US and we are going back there next week.
We have been preparing him for the move for some time, but he still has meltdowns about it. Have you ever heard of the book, "The Kissing Hand", well the same author wrote another book called "A Kiss Good-bye" or "A Good-bye Kiss". We read that book to both our boys quite often. It talks about always having the memories of your old house, friends, school and saving the picture in your mind. However, I am a scrapbooker and took pictures of every room in the house (from different angles) and taped as well, then, I took pictures of the movers packing (all three different pick-ups) and finally, pictures of the empty house. For now he is happy looking at these pictures on my camera, but when we get home I will make a special scrapbook just for the move.
Tomorrow we are taping/ and taking pictures of all our favorites places, on and off base ie. food, shopping, playgrounds, etc. Perhaps you could share this idea with your daughter and ask her to make a list of all her special places she wants to save on camera. (We even take pictures of our favorite foods!)
Finally, I left a small home town of 300 people a year after my mom died (I was 10). A year earlier another classmate moved and the girls threw her a going away party, but I did not get one (I only moved 60 miles away) I was devastated:( Plan a sleepover, party, etc. let your daughter help plan it or get the help of a few of her friends and through her a surprise going away party!
Best of luck to you,
M. R.