I think he’ll have a more informative tour if he sees the campus filled with students going to classes, and sits in on a class or two in his subject area. Sometimes you can get permission in advance to sit in on a class. You can probably check the academic calendars online to see when classes end.
When I was touring a campus with one of my sons, after finishing the tour, we went on our own into the computer science building and saw a room full of computers with students filing in for a class. Then my son spoke briefly to a counselor whose office was across the hall. We learned a lot from this short side trip: we could see that the classroom was way too small for the number of students and workstations; that the counselor was extremely friendly and helpful, as were some students we spoke to; and that the the teacher in the next classroom was difficult to understand because of his thick accent. These kinds of things added to our picture of what it would be like to be a student there.