Originally Google Classroom's were locked to the creating teachers account. Over time this has improved with first the ability to add a co-teacher and now the ability to transfer a class.
This is also key if a teacher cannot create a class. Create one yourself and transfer it to them.
To update the teachers ability to create a class as the School G Suite Administrator to complete the form 'Change Classroom Role' on the IT Assistance Portal itassist.nlesd.ca
Activity: Complete a Google Classroom Transfer
Review the attached materials.
https://support.google.com/edu/classroom/answer/7449476
To practise:
1. Create a Classroom
2. Add a seat mate as a co teacher
3. Remind them to accept the invite
4. Make them the primary teacher in the class (transfer ownership)
5. Remove yourself from the class.