Timeline: How the shooting at a Texas elementary school unfolded - ABC News
Phones at School Are a Disaster - The Atlantic
For students, smartphones are a lifeline in school shootings
Should cell phones be removed from school classrooms?
California education news: What's the latest?
Six killed, including three children, in Tennessee school shooting
Why number of US mass shootings has risen sharply - BBC News
Students Used Cellphones To Contact Parents During Shooting - CBS Colorado
Michigan teen pleads guilty to killing 4 in school shooting