If your school is a Google Apps for Education school you really should consider having students create digital portfolios in Google Drive. With 30GB of space and the ability to share a folder with your teacher Google Drive becomes a great place to house and submit content for grading and collecting digital artifacts.
Here is a brief tutorial on how your students can create shared folders from the iPad. Note you can follow the same steps to create shared folders on the desktop. Imagine the growth you will see over the course of several years.