If you have imported your classes with Google Classroom then you have the option to post your assignment and scores to your Google Classroom stream. After you create an assignment, choose the "Post Assignment and Scores to Google Classroom" option on your Share Assignment window.
This option will create an assignment in your stream, update the assignment on Google to show students' assignment statuses, and export grades to Google Classroom.
You'll be given the opportunity to edit your post before sharing it. We'll include a link that sends your students directly from Google Classroom to their CommonLit assignment.
If you decide later on that you do want to export grades to your Google Classroom gradebook, you can turn on this setting from your Assignment Dashboard. We'll prompt you to share the assignment on Google if you haven't yet to set up this exporting.