The Batch Script will allow you to bulk add Google Classroom Classes.
You will need to add the below information to the CSV:
I normally leave the 'alias' and 'name' as the same text string, 'section' and 'description' can also be the name.
If you have multiple teachers teaching the same class, complete this task and then look at Bulk Add Teachers to Google Classroom Classes.
@ECHO OFF
CLS
ECHO ----------------------------------
ECHO Creating Classes in SchoolName.com
ECHO ----------------------------------
cd C:\Gam\
gam csv BAT-CreateClasses.csv gam create course alias ~alias name ~name section ~section description ~description teacher ~teacher
ECHO -------------------------------------------
ECHO Finished Creating Classes in SchoolName.com
ECHO -------------------------------------------
Pause