This walk-out was in solidarity with walk-outs across the country - including at the school in Florida, where the deadly shooting occurred - to demand gun control legislation to prevent future tragedies.
Authorities from Palm Beach and Broward counties are following the students to make sure they are safe, a spokesman told the Miami Herald. He was known to be a risk for violence and state officials knew he meant to buy a gun.
The US Congress is also deadlocked on the gun debate, accomplishing nothing since the shooting in Las Vegas.
The three students were using a cell phone to film the other students who walked out holding signs and explaining why they chose to do so. In a letter to families, the principal of Bethesda-Chevy Chase said Wednesday was scheduled as a normal school day and that attendance will be taken in each class. "It has inspired Falmouth students". "I think a lot of us have the same mindset but it is just that step forward that we don't know what to do", said Dieuleveunt Biringanine, student body president at Service High. "So far, pretty much everybody is excited about it".
"We must move past cliches and exhausted debates and focus on evidence-based solutions and security measures that actually work", he said.
The poster had photos of the students killed in the Florida school shooting. Students are expected to stand outside for 17 minutes to remember the 17 lives lost in the shooting.
Up until now, he said, nothing has quite fazed them. She said she's communicated with students at Downey, Modesto, Ceres, Davis and other high schools who want to get their campuses involved.
"We're scared", said 17-year-old Molly Hetzel, who is organizing a walkout at Kennebunk High School. "It could have been my friends and my teachers".
At Dublin Scioto High School near Columbus, Ohio, about 200 students sat outside in silence for 17 minutes and wrote notes of support that will be mailed to survivors of the Florida shooting.
After walking past C.S. Porter, Big Sky students continued their walkout by joined students from Hellgate and Sentinel high schools at Caras Park.
"I started bawling and started crying to my mom, and we just talked together for a long time", she said.
Mashpee and Nantucket students have posted Facebook signups for students as well. "The importance of us doing this is to show students all over the country, really, that we have a voice".