Dress tends to be more casual than in school districts “Outside” of Alaska, but it also varies from village to village. Temperatures are not as extreme as in other parts of the state or nation. You should expect rain and mud in the Fall and Spring. Most find knee high rubber boots to be indispensable.
You will want a warm jacket, but may wish to wait and peruse through mail order catalogs or via the Internet, ordering when you can determine the type that will best suit your needs. Look for things that can be laundered, as your closest dry cleaner is Anchorage.