Google Classroom has an established training area on their Google Education Site
https://teachercenter.withgoogle.com/first-day-trainings/welcome-to-classroom
CPS Learning Technology Google Slideshow on Google Classroom.
https://docs.google.com/presentation/d/1d9qx1G1KHO9bnG5xrLvSKuRuqOXMRynL0ouj0D0Hnf0/edit?usp=sharing
This is a good video on how to use Google Classroom in an exclusive remote learning situation like now. The presenter explains the changes he made since he teachers remotely due to the ConaVirus situation.