You can create assignments from either your Google Classroom stream or from your Noteflight Learn account. In Google Classroom, you can post the score URL as a link in any assignment. Be sure to set the score permissions first and you can use Activity Templates for assignments requiring individual student copies.
In Noteflight, you may create an assignment from any score using the “Create Google Classroom Assignment” button in the Score Details panel. Once a Noteflight score is used as an assignment, all other sharing options are disabled to prevent duplication or confusion of assignment scores. As with all scores in Noteflight, you can “Save a Copy” in the score menu to create unlimited copies for other uses.
Assignments created in Noteflight automatically display in the Google Classroom stream. When students launch the assignment they can "turn in" or mark as done directly from the Noteflight score.