With school back in session for many American families, parents have new worries on their minds.  A new survey from Harris Interactive finds that more than half of parents are concerned about the safety of their kids in school.  Two-thirds of respondents say they worry about how their child's school would handle extreme weather or a natural disaster.  About 70 percent say they have fears about the recent rise in school shootings.  But many parents aren't taking steps to plan for an potential emergency situation.  Forty-two percent say they have no idea what their meeting spot would be in case of an evacuation, and over 60 percent aren't familiar with the guidelines their child's school already has in place.