After Sandy Hook, school year begins with security

School is back in session for the first full academic year since last year's massacre at Sandy Hook Elementary School in Newtown, Conn. Several metro-area school districts in Minnesota are seeking increased funding to improve security, and there is increased attention to safety issues throughout the school system.

But how much security is necessary? Is it even possible to make schools safe — and if we do, what kind of learning environment will we create?