The Longview school district will join a nationwide group that identifies students who could become violent and tracks them throughout their education — regardless of where they move. Longview ISD officials said Wednesday the district will participate in the Student Safety National Alliance starting in the 2013-14 school year. “What we are offering and introducing to you today is the Walmart for student safety and security,” said interim district Superintendent James Wilcox. About 70 school administrators and campus police officers from 25 school districts attended a school safety conference at the district’s education safety center to learn about the alliance....