The new version of iTunes U puts more cloud services to work. Version 3.3 now lets you add materials you’ve stored on cloud services like Box, Dropbox, and Google Drive. But you’ll need to have these non-iCloud services installed and signed in to import your files. If you’re a student, Apple’s Classroom app will now also guide you to specific iTunes U courses. Teachers, on the other hand, can also import class rosters from Apple School Manager. The app now also brings Explain Everything and Notability project files as course materials for the staff or hand-ins by students.
Source: 9to5Mac