Students and teachers returned to their school in Parkland, Florida, Sunday for the first time since the Feb. 14 massacre.
Yesterday, Marjorie Stoneman Douglas High School held an "adjustment" day for some volunteer students and teachers.
All teachers and school staff are due to return to work today to prepare for the resumption of classes scheduled for Wednesday.
"Imagine surviving a plane crash and having to travel by plane every day," 17-year-old David Hogg, who survived the massacre of Nicholas Cruz, told ABC.
Delaney Tarr, another high school student, said returning would be difficult. "It's worrying (…) and scary because I don't know if I will be safe there," he told Fox News, "but I do not know what to do.
A teacher who returned to school told state radio station NPR that she was so shocked that she saw the room exactly as she had left it during the incident, with the students' notebooks open on their desks and the diary still writing on February 14, which made her ill. and was forced to run away.
Cameron Casky, another student who also survived, posted on Twitter a photo of people returning to school and the comment: "It's nice to be back."
"All my friends are here with me and that makes me not feel alone in this situation," Michelle Nitmeier told ABC.
Former students had also gone to school yesterday to express their support for the survivors and raised banners in the building, WSVN reported.
In the neighboring city of Fort Lauderdale, it was organized overnight yesterday, with 17 chairs left empty in the memory of the victims, according to WSVN.
At the same time, a demonstration took place in front of a factory in Pompeo Beach where Kalashnikovs are made.
"Immediate reform of the weapons law!" Wrote one of the protesters' banners, while another called for the closure of the "death factory".
Two rallies are planned in the coming weeks: all students in the country have been called to protest on March 14, leaving their classes for 17 minutes.
A large rally is scheduled for March 24 in Washington to demand tighter controls on arms sales.
According to a CNN poll conducted after the Parkland massacre, more and more Americans are in favor of stricter gun laws, as well as a ban on semi-automatic weapons, such as the AR-15 used by Cruz.
Overall, 70 percent of respondents from Feb. 20 to Feb. 23 voted in favor of stricter gun sales controls, up from 52 percent in October after a Las Vegas concert massacre, the deadliest in recent US history with 58 dead.
In addition, 57% were in favor of banning semi-automatic weapons, compared to 49% in October.
Police had located 14 AR-15s in the room of the perpetrator of the Las Vegas massacre.