Depending on who you are, your login credentials vary.
Teachers and school staff members use their work email address to log in. This can be used in conjunction with a Schoolrunner password (to reset your Schoolrunner password, review this article). If your work email is hosted by Google, use the Google sign-in button to gain access to Schoolrunner.
Parents and students log in with credentials provided by the school. Credentials come in the form of A) a username and password, B) a Google email address, or C) a Clever email address. Your school determines which one of the three forms you will use. Learn more here.