Begin by visiting launchpad.classlink.com/lcusd and on the login page, enter your username (first part of LCUSD or mylcusd email address, ex. jbauer24 for students or mmouse for staff).
Next, enter your school password and click sign in (do not use sign in with Google yet).
After hitting sign in, look to the top right and click on the profile picture. This might be just a blank face if you are a new user. Then click on SETTINGS.
Next, click on "Sign In" along the top.
Click on the blue chain link icon above the Google account option. A window will open. Sign in or select your school Google account if you're already signed in. You should then see the blue chain link icon turn red. Going forward, you can now login to Classlink using the SIGN IN WITH GOOGLE button or with username and password. Both work.