We are using this and another "secret" project from Google. Coursekit is great for sharing individual documents within Moodle. It doesn't share folders. We are getting teachers involved in trying out the coursekit assignment where they can turn in a google doc and teacher can grade and markup the doc within coursekit.
It's basically a frontend to share and distribute Google Drive docs. It is nothing more than an LTI connection to get started. Very easy and simple to setup. All of 5 minutes and you are ready to go.