If you wish to join a Class with a code you should go to www.peergrade.io/join, type in the code provided by your teacher and click Next.
When you have typed in the code you have two options. If you have not used Peergrade before you can create a new account. If you already have a user you can log in. Choose one of the two options.
If you choose to create a new account you can either sign up through the form or by using your Google sign in. When you have completed the sign up process you will be directed to your Class or Live Session.
Note that you won't receive notifications or be able to reset your password if you choose to sign up with a username instead of email.