When someone joins a class via text, they'll get an automatic notification with the class owner's display name. Each class announcement will be labeled with the class name, while individual messages will be labeled with the display name. 

Here's how it looks.

Messages will come from a different phone number for each teacher.

For example, announcements and messages from Ms. Smith will come from one number (555-555-5555), while announcements and messages from Mr. Jones will come from a different number (888-888-8888). You can save these numbers in your contacts list under the teacher's name. 

The area code for these numbers is randomly assigned and doesn't change the normal cost of receiving a text message.