We do NOT recommend students who are staying for only one semester to apply for an ID number.
However, students staying in Norway for more than six months will need to report their relocation to Norway and get a National Identity Number, also known as I.D.-number.
Step 1: Pick up your residence permit/register with the police as soon as possible after arrival.
Step 2: After registering with the police, you must as soon as possible go to the Tax Office (Skatteetaten) in Kristiansand or Grimstad to report your relocation to Norway. You must fill in the form "Notification of relocation to Norway from abroad". Please see this webpage for the form and for information on what documents you need to bring.
Step 3: When your relocation has been correctly reported, you will automatically receive a National ID number within 2-3 weeks.
Step 4: If you wish to open a bank account, you may do so after having received your National ID number. There are several banks that provide good service and where you can open an account. SpareBank 1 SR-bank is just one example: