Our solution was to create a Google Form that will collect the shared links of the students' work. For example, Maddie would complete a Google Presentation concerning the geometry lesson they were studying for a grade. Maddie would copy the unique link that allows her to share her presentation and place that link into a pre-made form that collects each link. Maddie would paste the link into the form and press submit. Mr. Biggers will receive a spreadsheet of all of the students names and links to their assignment. When it is time for grading, Mr. Biggers will click the link of all of the students presentations in the spreadsheet and grade them inserting comments in Google Docs. The feedback will be automatically posed in the students Doc with a grade. This way no one sees the work of each student, except for the student and teacher.
Check out the video below to get an idea of this in action.
Access Mr. Biggers math course by the link here (shared folder with course modules)
for more on Google Apps for Education see www.21learning.net and check out my up coming book Google Apps Meets Common Core
If you have any questions about this please contact me at firstname.lastname@example.org