US schools take hard-line approach to shootings

Tough measures adopted to safeguard students and teachers

As schools reopen across the United States after the summer vacation, the mass shooting at an elementary school in Uvalde, Texas, is fresh in the minds of parents, students, teachers, administrators and first responders.

The rampage on May 24 at Robb Elementary School, which left 19 children and two teachers dead, was the deadliest school shooting in the US since the attack at Sandy Hook, Connecticut, in 2012.

The Uvalde shooting led to public school districts nationwide "hardening" security to protect the nation's more than 50 million students. "Hardening" is an industry term referring to adding layers of security to schools.