What to Bring
You will want to make sure that you have a few summer outfits to get you through the last half of August and all of September. After these two months it starts to get really cold. You will want to have plenty of sweaters and long pants. Once it gets cold in France, it pretty much stays that way until April or May. 
Do not listen to what anyone tells you when it comes to the winters in France. Even though Aix is by the Mediterranean, it gets unbelievably cold in the winter, sometimes as low as -7C. Though it doesn’t really snow in Aix (2 times in the two years I lived there), it does have a freezing wind called the Mistral. Generally, it blows in 3, 6, and 9 day increments. This wind will drop the temperature a few degrees in a few seconds. I didn’t believe it until I lived there and watched everyone become sudden statues as it picked up. Bundle up good if you look outside and the wind is blowing! 
Buy Your Winter Items When You Are In Aix
You will probably want to buy your heavy jackets when you get there. Make sure that you invest in scarves, gloves and hats. You will be wearing them every time you leave the house. The key to staying warm is layers.
Try to bring only those things you can’t live without. Don’t buy a lot of your kids’ winter clothing in the states and pack it. It will make your luggage too heavy and chances are you might not pack what is needed. We Californians don’t know how to dress for a real winter! Buy most of their clothes after you arrive. 
There are some good and inexpensive places around (look under Shopping) and the clothes are better made there to suit the environment. They will also be in style with the other French kids! Have the kids pack a few of their favorite toys and things. For my kids, they each got two suitcases. One was for their clothes and the other was for their toys. They also were given a backpack for a carry-on which contained their lunches and what they wanted to do for amusement on the plane.
If you use a hair dryer or iron, don't bother packing it. Those items and other small electronics are easily found at the hypermarkets. They are inexpensive and this way you don't have to ship them or buy the adapters.
