Answer:
For Caribou Contests to be fair, participation should be done at a school, library or home school which needs a contact person to register (for free).
If you are a student and can not find a school, library or other public institution that would register through a contact person then please have a look at 'I am a parent' --> 'Participation' --> 'My ...'.
If you are a teacher with a single student voucher or with a school wide voucher and do not have an account, then create one by going to the 'Contacts' --> 'Contact Registration' option in the menu on the left.
If you are a teacher with any kind of voucher and have an account, sign into your account by clicking 'Contacts'. Once you have signed in, click on Redeem voucher codes which is located under Access Code Management. Enter your voucher code into the appropriate form, then click 'Submit'.
If you have more questions, please investigate this help page further.