The rubric feature in Google Classroom allows teachers to design custom rubrics to provide students with learning targets as well as feedback on assignments. Rubrics can be as detailed or simple as needed, with the ability to reuse old rubrics on new assignments.
In my math classes, I provide students with a 3-2-1 rubric that outlines the targets. The link below is a screencast of how I go about creating my rubric and then what it looks like on the assignment.
6th Grade Teacher
Virginia Parks Elementary