I just tried this new feature and it is
awesome! My school is part of a GAFE district so being able to "sign in" via Google is great for my students. Today my son was trying to program a "star" mission and being able to go back to the 8-point star he originally created then troubleshoot his angles to create a 5-point star was helpful.
One tip: Before you or your students start coding, go ahead and login. I tried logging in to save after creating a test mission, my iPad froze and I had to restart the app. I didn't lose my mission but just in case...log in first and save periodically when working on a lengthy mission!