Class Keys and Activation Codes now include one of the following prefixes to help you tell them apart. It does not matter if you include the prefix when using the codes.

ck-xxxxxxxx

This is a Class Key. Students use this to join a class.

pr-xxxxxxxx

This is an activation code. Teachers use this to activate seats on their accounts or distribute them to other teachers.

bp-xxxxxxxx

This is a bookstore code. Students purchase these from their school and use them to activate their seats.