Teachers after Texas attack: ‘None of us are built for this’

Teacher Jessica Salfia was putting up graduation balloons last month at her West Virginia high school when two of them popped, setting off panic in a crowded hallway between classes.

One student dropped to the floor. Two others lunged into open classrooms. Salfia quickly shouted, “It’s balloons! Balloons!” and apologized as the teenagers realized the noise didn’t come from gunshots.

The moment of terror at Spring Mills High School in Martinsburg, about 80 miles (124 kilometers) northwest of Washington happened May 23, the day before a gunman fatally shot 19 children and...