Some local school systems have gotten early Christmas breaks because of the recent snow. But why does one school system call a snow day, while schools in a neighboring county are in regular session? Much of the answer lies in the topography and size of school districts in Northeast Tennessee and Southwest Virginia and the way snow systems travel. Last Friday, for example, Winter Storm Benji moved across the southern part of the country, bringing snow to states that rarely see it. In Northeast Tennessee, Hawkins, Carter and Washington counties got their first measurable snow of the season, and Hawkins County schools dismissed early. But Kingsport and Sullivan County got just a dusting and were in regular session the whole day.