The No Email Emailing Solution

I'm an optimist. I believe that one day, there will be a flawless system for sharing all kinds of files across devices. I will not need to use Dropbox for large files, iCloud for files created on Apple apps, Google Drive for documents, and email for when all else fails (or  I want students to avoid navigating yet another app.) Until that flawless system is invented, what do I do when I have shared iPads and students without email accounts? Hence... the no email emailing solution:

• Create one email address for the grade or class. Ex. sharedipads@yourschool.org
• In the email account settings, specify that outgoing mail may only be sent to sharedipads@yourschool.org
• Specify that incoming email may only come from sharedipads@yourschool.org, and from your email address
• Install the shared email account on the iPads
• If you need to share a file with the entire class, email it with the subject line "whole class"
• If you need to share a file with one student, email it with that student's name as the subject line

Have any other easy file sharing solutions? Please share!