So now if you want to create or join another user's class in Google Classroom, you can! Here are a few thoughts on how it can be used...
Home-school
If you are a parent who home-schools your children, Google Classroom can be the perfect space for you to post links to online documents, videos, and other resources. And if you have more than one child at home that you teach, you can differentiate between students by assigning work specifically to the child that needs it.
After School Clubs
If you are a club sponsor for a school, or volunteer for an organization, but don't have access to Google Classroom as part of a Google for Education District, you can use Google Classroom on your personal Gmail login. Keep track of club members, post announcements for your club, and share videos of your events through classroom. Plus, since you can email directly from Classroom, you can keep all of your members up to speed on important dates.
Online Courses
Have you always wanted to offer Online Professional Development to fellow teachers outside of your district? Do you have a consulting business and have a need for an online learning management system? Try using Google Classroom. Since it is now open to consumer users, anyone can join your class.
Organizational Meeting Space
If you are a member of an organization that meets regularly (think Rotary Club), you can leverage the tools in Google Classroom to carry on discussions related to important topics in our organization.
PLC Sharing Space
Are you part of an online PLC for education? Previous to the new updates for consumers, users had to be part of the same domain to use Google Classroom together, or at least they had to be approved by a domain. Now you can use Google Classroom and share ideas with anyone in your PLC, regardless of what school or district you are from. Try using Classroom as a discussion board, chat room, or a place to curate and share resources. Just make sure to set the Student settings so that all students can post and comment. This will allow all users in the PLC to post and reply to one another.