The following comes from the book Shortest Way Home by Pete Buttigieg. He is explaining why he frequently visits local colleges and universities:
I go partly because I just enjoy engaging students, who tend to ask the most urgent and penetrating questions, but also because they represent the key to a transformation now underway in what it means to be a college town.
In the sentence above, I'd like to know what this means and how the structure is composed: "in what it means to be a college town".