How can I tell if a classmate is online?

A green circle besides the name of a classmate indicates that that user is currently online.

How do I send a classmate an email or message?

A message can be sent to a classmate by clicking the listed email address of the classmate. An email window will popup allowing you to send this user a message.

How do I access another users locker?

If a classmate has files in a locker that are PUBLIC, a locker icon besides their name will be available. Select this icon to be taken to their locker.