Hear, hear! I use Duolingo for new languages and their system of spaced repetition is so vastly better than Ms. McGee's that I wouldn't even think to enroll a student in a class anymore. I was using Duolingo to study Italian before a trip to Milan and even then using the app was nearly pointless. All it did was get me started in the grammar and some basic words, but actually being surrounded by Italian, seeing it on every billboard, every menu, every streetcorner, having almost no-one speak to you in English (if requested), THAT got me good in Italian. If we simply wanted to take a random assortment of children, fly them to #Country# and let them live there, that would get the language and culture into you.
Reading this back, actually, that is what I think I'll do with my kids then. We have family all over the world, speaking a variety of languages, we should just have the kids go there for a month each summer. In the end, it'll be less expensive, maybe....