OWlbox
There is a Facebook-like feature where you can comment and exchange feedback on files you are sharing. The box service automatically keeps previous versions of the documents. In addition you can assign tasks to a shared file and supply a due date.
Please make sure that you send all assignments from your @temple.edu email account and keep the sent message for the duration of the semester in case confirmation is needed. You should receive a confirmation from OWLbox that your submission was received as