Apple iOS - iPhone or iPad
For Apple iPhones and iPads, you can download the google classroom app using this link: Google Classroom
Once downloaded, you will open the app and log in using your student's Google account and password.
Once logged in, you will be shown a list of the classes your student is enrolled in.
You can select the + sign to add additional classes when you have a class code
Clicking on a class will present you with the activity feed for the class with any posts made by the instructor and any assignments will be listed.
From the Class List, you can view different students by using the icon in the upper right corner and adding or changing accounts.