I do not know what subject you're interested in, so I will suggest something that is important in education, pertinent to the new teaching techniques, and applicable to all teaching subjects and styles.  That subject is diversification.  We all have different learning styles and different interests. You could ask: When you have a classroom of thirty students, how do you diversify to create an atmosphere of learning that is beneficial to all students and that can be managed successfully by the teacher? 

As an example, in the field of language arts, the teacher might be teaching the genre of historical fiction and its elements.  It may be on a specific historical period or just historical fiction in general. The students are allowed to choose the book they wish to read from a list provided by the teacher.  The teacher then divides the students into four or five groups based on the top four or five novels chosen.  The teacher determines who can work together, and what needs to be learned and then develops identical or similar assignments.  How can you handle this so that the paperwork does not overwhelm the teacher?  It is not an easy task and much more complicated than I have made it sound in this answer. This is classroom management at its best.