Advice for first day of school?

well I lived in Boise, Idaho until i was ten and then moved away for almost five years. I have caught up with some of my old friends, but I'm scared of what the other kids that were in elementary school with me and everybody else will think fo me, especially a really nice guy that i know will go to my school and since the lockers are in alphabetical order by last name, lockers close to each other. Advice?