If you actually want to go to this school, ask genuine questions about stuff you're thinking about. Some examples:
How easy is it to get an internship there?
How available are on-campus jobs?
How do most students get around campus?
Is there anything about this school that you think is understated in recruiting material?
Is there something you can say you think the school could do better?
There's no shortcut to this. The interviewer is looking to see that you're genuinely considering going to their school, and they're looking to learn more about who you are as a person.
That last question is particularly valuable. I was choosing between University of Michigan and Northwestern University for their engineering programs, and I asked the Dean of Engineering at NU that while on a campus tour. She explained that their engineering program was growing pretty fast and they didn't hire on enough faculty to compensate, so it might be a bit harder to get into the classes I wanted to. I really appreciated her honesty and I ended up going to UM instead (for a variety of reasons, but that was one of them)
While admissions officers might want to coax you onto their campus, other school staff don't really benefit from having a student who's unhappy with their decision, so if you're going on campus I'd encourage you to talk to a dean.
