Open Classroom and click the "plus" sign.
Once a student responds, then he or she can see other comments and responses. After a student submits the comment, you get an email notification of the post.
You can also use Classroom to poll your students. Mary Catherine often uses this feature as a bell ringer.
The process is similar to creating a discussion board
- Go to the plus sign
- Click create question
- Hover over "Short Answer"
You could use the polling feature as a bell ringer as Mary Catherine Keating sometimes does, or perhaps as an exit ticket.
Here's a blog post from Google for Education about the polling feature.