To begin, launch System Settings and log into your district Managed Apple ID (this is the same username and password as your district Google Account)
Next, launch Self Service and install the Classroom app.
Once you are signed in you should see the classes you have rostered in PowerSchool.
For student iPads to become accessible in Apple Classroom, they also need to be signed into their district Managed Apple ID.
First launch System settings and sign into their district Managed Apple ID. Again, this is the same as their district Google Account.
After they are logged in, an Apple Classroom pane will be added to system settings showing the classes they are enrolled in in PowerSchool.