If you want to leave simple feedback for your students, you can leave a text comment directly from the Gradebook.
Open Grade Detail Tray
Locate the student name and assignment where you want to leave a comment. Click the Gradebook cell and click the Grade Detail Tray icon.
Where there is more than one comment for an assignment, comments will be listed in chronological order with the oldest comments appearing at the top and the newer comments appearing near the bottom .
To delete your comment, click the Delete icon .
To edit your comment, click the Edit icon  and make your edits in the comment box . When you have finished editing your comment, click the Submit button . The time stamp of the edited comment will indicate the comment has been edited .