A simple workflow for managing student work is so important when using iPads in the classroom. Schools are finding Showbie provides a great solution, and with recent updates it's definitely worth a look. There is an app for iPads and it works via a web-browser on Mac, Windows, Chromebooks and Android.
Your teacher account is connected to your students' accounts through your "class" on Showbie. You can distribute documents and resources, and students can save their work from a wide range of apps either to "hand-in" their work to you, or simply for safe keeping before the shared iPad goes back in the trolley.
When students have completed their work they can "send it" to Showbie for you as their teacher to view and mark. Equally as valuable, unfinished work can be "backed up" to Showbie rather than risk it being deleted on a shared iPad. Using the "Share" icon, select the "Showbie" icon to upload: