How do school officials decide when to cancel school?

More than 140 school districts canceled classes on Thursday and others ended early. And as the current winter storm continues to dump blowing snow across much of the state, many students and parents are be expecting more class cancellations on Friday. To find out how some school districts evaluate whether to close their schools, All Things Considered host Steven John talked with John Landgaard, the superintendent of the Worthington Area School District.