(WJRT) - (02/21/18) - Does your child carry a rubber 'door stop' in their backpack?
A security expert behind the suggestion says if a gunman shoots out the door lock it will still keep the door from opening and may just buy them some time.
A Connecticut mother took to Facebook to encourage others to do it. It's something her nieces started doing after the Sandy Hook shooting in 2012.
The post went live the day after the Parkland, Florida massacre and has since gone viral and has been shared now more than 1.4 million times.
In a follow up message Katie Cornelis says, "I'm on a mission now to get this message to schools across America so each classroom will have one and every child will have one in their backpacks. Thanks for all the help everyone. There IS strength in numbers. Keep it going!! #actionsnotjustprayers"
The original post can be seen along with this article.