Depends on the instructor, the school, the admin, the state, etc. This is actually a huge blind spot with the approach. We have a friend that's a college instructor that will turn students away if they don't do the material. Flipped works great in that environment. Not so much when you're a public school teacher in a state that cares about standardized test performance and advancement at all costs while also cutting their education budgets and, consequently, forcing teachers to wrangle 30+ student classrooms...

Thread on the topic: https://old.reddit.com/r/Teachers/comments/1958imi/what_are_...