Dec. 17, 2012 -- Teachers and students across America confronted the issue of safety and security in the classroom today after a weekend of grappling with the deadly massacre at a grade school in Newtown, Conn.
A day of jitters led to many false alarms. In schools from New York to Tennesse to Texas hyperalertness resulted in reports of bomb threats and even an umbrella being mistaken for a gun.
One threat took place just 20 miles from Sandy Hook Elementary School, the scene of Friday's massacre.
"It's very important that we address their concerns [about safety]," teacher Lauren Marrocco of New Jersey said. "I think my students will have a lot of questions and, as adults, we don't have answers to those questions."
Near Newtown, one teacher's weekend homework for students was simple: Go home and hug your loved ones.
In California, where the day started with a mock lock down drill, another educator wrote, "I'll be locking my [classroom] door this week to make my students feel safer."
For many, this morning's school drop-off was a difficult but necessary start to the day.
"I'm not too worried about her, I'm more worried about how I feel and how I'm going to let go of her hand when she gets on the bus," a parent told ABC News.
In Fairfax County, Va., schools sent notice that they would be upping security, not for any specific threat but to alleviate anxiety, and in Pennsylvania, school security guards now have guns.
"The difference is on Friday we weren't armed, on Monday we are armed," school security officer Nick Kovalsky said.
Dr. Steven Marans, head of the National Center of Children Exposed to Violence at Yale University's Child Study Center, said that falling into normal routines can provide comfort.
"One of the ways of demonstrating that their lives are secure and reliable is to have them disrupted as little as possible," he said.
Marans says it is also important not to avoid discussing Friday's events, in which 20 children and seven adults were killed before Adam Lanza took his own life.
"We need to acknowledge that we all have big feelings," he said. "This is very sad. This is an opportunity for kids to put into words what they're thinking about."