There is much more information to learn in major courses than 30-50 years ago, and the increadingly easy accessibility to facts on the Internet is making long-term memorization of details less and less important. When students branch into their careers they will be expected to apply what they've learned to problems in real life and working in collaborative settings. Therefore, teaching for conceptual understanding and analytical skills while encouranging collaborative activities makes increasing sense in undergraduate courses. It's not just about having an interactive classroom to get students to pay attention, but to learn efficently and build long-term memorization.