With some of the changes to Canvas over the past year, our students (who have used Canvas Student on an iPad for 7 years) are finding more difficulties with the native annotations on PDFs. We've been migrating some teachers to use the "Student Annotation" submission type. While the "Student Annotation" submission type is doing a much better job of holding annotations when someone comes back to an assignment, one of the biggest requests is that after a student submits their assignment, the teacher could allow students to revise their work. As it stands now, a student cannot pull up the PDF again with editable annotations. 

Here's how I imagine the workflow would work best.

1. Student clicks "Submit Assignment" to open the PDF of the assignment, annotates on the assignment and submits the assignment to the teacher.

2. The teacher, in the Canvas Teacher app, grades the assignment, sees that a student could make changes to the assignment and would like to give them another attempt. 

3. Teacher clicks "Reassign" button.

4. Student goes into the assignment and clicks "Resubmit Assignment" - when they click into that assignment, the annotations from the previous submission appear and are editable.

5. Student makes the changes and then submits.