Good questions. I just gave some old fashioned advice to one of my college students who was going out for an interview in which she got the job. These suggestions may strike you as odd, but they work and are based on solid research.
1. By the time you are being interviewed, the school or other employer has already decided you probably have the necessary skills, so that question is not always on the table.
2. The real question is personal chemistry.
3. Happily or sadly, you can "game" the chemistry issue by two tricks. First, check out the employer before you go for your interview and be sure to dress just like the people who work there. They will feel you fit in if you look like them. Second, keep your head moving. Psychological research has shown that interviewers will form all kinds of positive impressions if you keep moving your head.
4. It does sound as if you have had some good interviews in which serious questions have been asked. Obviously the question about students who "act out" is getting at your age and maturity and also telling you something about the challenges the school is facing. I'd suggest that you respond to a story question with a story answer. Confidently describe a time you managed a tough student, while quickly going over in your head a principle or two that you ought to demonstrate. As a person who hired professors for years, if I asked a question like that, I would have been looking for a relaxed answer that showed me the prospective employee had seen it all and could comfortably manage any challenge.
You will no doubt have noticed that there is a problem with the hiring scenario I have described. When the main question is personal chemistry, or how a new person will fit the group, the unspoken agenda works against hiring people who are different in any way: younger, older, of a different race or ethnicity. That's how structural discrimination works. Once you know that, however, you can try to set people at ease and show how well you fit--even as you may understand that you may be swimming upstream.
There are lots of different types of interviews. What I have said applies best to the informal individual or group meeting. Panel interviews that are run like Olympic competitions can be different. Good luck.