<p>I agree with ingerp! My daughter wore her regular t shirt and jeans to her “interviews” and she was dressed just like the other kids there. And she was comfortable for the campus tour. I do think if you are having an interview for a scholarship or an alumni interview you may want to step up the wardrobe to business casual( nice pant/skirt, shirt).
There will be those who disagree with this, and I think it probably does depend somewhat on the school you are going to. My d is not interested in any top tier schools or schools with “preppy” atmospheres, so the vibe on campus is probably more casual. Since you will be visiting in the summer he might be very uncomfortable walking around in dress pants and dress shoes. You can always call and ask the schools what would be appropriate!</p>