By Mike DeNardo

PHILADELPHIA (CBS) — Parents who have electricity may be wondering why their entire school district had to be closed this week even though the lights were on at their local school.

Unlike a snowstorm, Hurricane Sandy left an ever-changing patchwork of areas with and without power.  And a good number of entire school districts were shut down (26 area districts today).

Parents may see their individual school with the lights on and wonder, why did it have to close?

After being closed all week, nine of the ten schools in the Lower Merion School District have reopened.  But spokesman Doug Young says that all week the district was dealing with bus routes hampered by downed trees and power lines.

“The decision to close was a relatively easy one,” he tells KYW Newsradio.  “If you can’t get kids safely to school, and if many of the schools they’re arriving at don’t have power, you just can’t operate your school system.”

Young says other considerations included Internet and telephone outages, and power to bus depots.