On Dec. 14, 2012, a young man killed 26 children and adults at Sandy Hook Elementary School in Connecticut using semi-automatic weapons from his mother’s home.

On June 7, 2013, another young man went on a shooting rampage at Santa Monica College after killing his father and brother at home.

Just last month, a student killed nine people at Umpqua Community College in Oregon before turning a gun on himself.

These and other high-profile school shootings have sparked debate over gun control laws in the U.S. and fueled discussions among educators and other public officials about keeping campuses safe.

Last month, Santa Monica-Malibu schools Superintendent Sandra Lyon joined colleagues in urging stakeholders to help prevent future attacks at school.

Lyon issued a memo to parents and guardians to remind them of California laws regarding children’s access to firearms.

“There have been many news reports of children bringing guns to school,” the memo reads. “Many times the child has obtained the weapon from his/her home. These incidents can be easily prevented by storing firearms in a safe and secure manner including keeping them locked up when not in use and storing them separately from ammunition.”

Lyon’s memo arrived as communities across the country took part in America’s Safe Schools Week, a national effort to curb gun violence and promote safety at educational institutions of all sizes.

The outreach effort came after a May directive from Tom Torlakson, the state superintendent of public instruction, urging school officials to inform parents and stakeholders about California’s access laws.

Nearly 70 percent of recent school shootings involved the perpetrator bringing a firearm from home to campus, according to an analysis cited by Torlakson.

“When it comes to gun violence, schools cannot do it alone,” Torlakson wrote to administrators and school leaders. “The California Department of Education and the education community are dedicated to making our schools the safest in the nation, but it is the responsibility of parents and guardians to store firearms according to California law. If California’s child access prevention law is to be practiced more widely throughout the state, we must all work together to prevent future tragedies.”

California has had child access prevention laws since 1992, according to the California Chapters of the Brady Campaign to Prevent Gun Violence. Assembly Bill 231, which took effect last year, makes people criminally liable “if they negligently store or leave any loaded firearm on their premises where a child is likely to gain access to it – whether or not it is brought into a public space,” according to the Brady Campaign.

“Keeping our children safe is a shared responsibility that starts with educating parents and guardians about proper, responsible storage of any firearm in the home,” Peggy McCrum, state leader for the Brady Campaign, said in a press release.

For more information, visit www.cde.ca.gov/ls/ss/sa.