Nordic citizens (Swedish, Danish, Icelandic or Finnish) who plan to live in Norway for less than six months, do not have to report a move to the National Registry nor go for an ID check.
However, students planning to stay in Norway for more than six months must report a move to Norway and visit the Tax Office for an ID check no later than eight days after arrival in Norway (external link). In addition, students must deliver a copy of the confirmation of immigration from Skatteetaten to the International Office at one's Campus of study. Drop by the Office or forward a copy by e-mail.