tufts seems to care a lot about demonstrated interest, so I’m wondering if they track campus visits
Have you Googled “Common Data Set” set for Tufts? Do that for almost any school you are interested in and you will see that there is a section on how they consider various factors in admission, including student interest.
Any school that says they consider it does take note of who signed in at admissions for a visit. Even those that don’t use interest seem to require sign in for tours, but you can’t know if/how they use it.
There are other ways to show interest if you can’t visit, though.
I believe so since when I toured Tufts nearly 3 years ago they made me sign in and then when one of the admission officers came to visit my high school, he had a list of students that had already visited the campus, so they definitely keep track of it.
I think they do.