This year we are more organized with Google Drive Folders.
Here is our process:
I also created a GIF so that students can see how to "add the folder" to their Drive. This GIF was created with my ever increasingly favorite app, Workflow. You can get the workflow here and add it to your collections of Workflows.
While making the movie in iMovie, it's very helpful to have the "activity feed" up on the screen. It notifies us of changes to the folder.