In a traditional classroom, students gain new information by reading a textbook or listening to a lecture. They are then assigned homework to practice using the new information or to reinforce the knowledge and increase retention.
A flipped classroom is one in which this method occurs backwards--the students are given the new information at home, by way of video lecture hosted online, and then have the opportunity to practice or reinforce in the classroom.
There are some drawbacks, of course, such as how it takes time to create the videos and upload them, how it's an initial investment to purchase the software and hardware to create the videos and the space to upload them to a host, how all students must have internet access at home, and how the student that doesn't do his work will be lost in class the next day.
But overall, it seems like the positives outweigh the negatives. The videos, which are typically similar in style to Khan Academy, may be paused or watched again and again in order for a student to focus on a confusing concept. It's like a personal tutor.
(Yeah, in the case of a bad video lecture, a student may be confused and have no way of asking a question like they would in the classroom, but that can be handled with a system to contact the teacher or professor or a forum in which the students can help each other. Or all questions can be written down to be discussed in class the next day. My philosophy is that if one student has a question, others are thinking the same thing but are too shy to ask. So if it IS the case of a bad video lecture, it will have to be recovered in class, regardless.)
The point of the video lectures is merely to introduce new concepts that will be discussed and played with the next day. The students shouldn't be required to memorize information or even fully comprehend the material--the only thing they need to do is watch and absorb as much as much as they can. Isn't that the nature of an in-class lecture, as well, though? Just absorb as much new information as possible? The real learning comes from the application of that knowledge.
And that's where the big advantage comes in. Because the application of the knowledge is where true learning happens, the flipped classroom puts this in the classroom, where teachers and professors have more control over activities and discussions and can clear up any misunderstandings or go into more depth. The learning becomes more significant because no longer is it done a home, sleepy and alone, in one's room. Rather, it's done with peers, in the excitement of daylight.
The initial attainment of information is the easy part. It can be done at home just as easily (with the properly prepared instructor) as it can in the classroom. The critical part is the application of knowledge and in depth exploration. It can be done at home, but teachers in a flipped classroom would argue that it is much more effectively done in the classroom, with peers to discuss with and teachers to guide and clarify.
There is a myriad of resources available online that go into more detail, but that's the basis of it and all I feel necessary at this point. I'll link below to any specifically good articles if I find any.
I've been thinking about flipped classrooms recently as I've been preparing for my first year teaching. I don't think I'm prepared to jump face-first into anything, but I'm seriously considering including some adaptations. I'm not a big fan of homework, and I had decided a while ago that the only homework I wanted to assign was reading. I still want to do that, but.. well, as a first year teacher, I'll be teaching from textbooks. I'd hate to devote a lot of classroom time to merely reading textbooks, so I thought, "What if I had the kids take their textbooks home and read just a chapter?" They wouldn't have to memorize it or anything, like I mentioned above, but just get a general gist of what we'd be talking about the next day. I think it's entirely reasonable, and I don't see any problems with it.
Of course, there'd definitely be some students that would try to get out of it. I could require a parent signature, but that's beside the point. When I was in school, I remember being given reading assignments and not completing them. Honestly, I got a good understanding of the material from the class discussion the following day. If that works for my students, who am I to complain? I'd still assign the reading, and expect a good discussion. If the discussion went poorly or if students showed obvious signs of lack of comprehension during other formative tests, then we'd have to do something different, such as requiring parental signature. Or looking into the situation to discover what was going wrong. But that goes without saying, as that's just good teacher practices.