If you plan to use Google Classroom, use this guide instead.
To get started making a Boom classroom, go to the Classes tab and select New Classroom to make a new Sign in with Boom classroom.
Your classroom will be automatically generated with a username and password. You can click on the username and password to change them to your liking.
Note: usernames cannot have spaces, and are not case sensitive. Passwords can have spaces in them, but are case sensitive.
If your students are old enough to make their own accounts, you can give them the classroom URL shown underneath the username and password, or they can go to http://Boom.cards, click Sign In With Boom, and enter the classroom username and password. Then they can click "New Student" to get their account set up.
When all your students have their accounts set up, you can Lock the classroom, preventing students from changing their avatars and names, and from making new accounts. Students can still change their password in a locked classroom.
Caution: do not distribute the classroom URL if you need to keep the classroom roster private. For more information, see this article: Keeping rosters private - FERPA & HIPAA Compliance
For younger students, see Adding students to classrooms manually (for younger students)