Google Drive is an absolute must in any classroom. It allows student file storage, is easy to use, and allows student/teacher collaboration. The only issue I have had in the past is when students don't share a document with me correctly and I do not have access to edit or to view a file. Remembering to type in a long email address or granting proper rights can be problematic for younger students. There is an easy way to avoid all this. Instead of sharing each file individually, students can create a folder in their Google Drive and share that folder with teachers. Then, any file they drag/create within that folder is automatically shared with those who have access to it, and all rights granted follow all files. Easy! Below is a short video on how to do this. Check it out!
How to create and share folders to share files in Google Drive.