More colleges are adopting policies to discourage—or in some cases ban—students from being on campus in January. Generally, the colleges that are acting start up the first week in January. Institutions with later starts tend to be waiting to decide. DePaul, Harvard and Stanford University students won’t have in-person classes the first weeks of the semester, those universities announced; Pennsylvania State University, the University of California, Los Angeles, and the U of Southern California are considering such a move.