As you pack your room, make one box be the most important one. Leave it for last and label it "Open me first". It should have all your first week plans and forms, letters, games, and things to go home.
With any luck you are able to make copies of what you need for the first week. Also in this box, include immediate supplies - pencils, paper, crayons, scissors, glue, stapler, pencil sharpener, etc.