But I think if you really are just starting out learning programming then it's still a lot of effort to get a Rails system up and running (you need a database, too, which is another new thing) compared to the bare minimum, which is to use something like Meteor, Firebase, or even (gasp!) Mongo.

I'm not saying that Rails has no place, and it might well be the best next step, but I wouldn't put it (or Django, maybe Express) in a course for absolute beginners. Perhaps in the follow-up course :)