(CNN) For these 3,000 teens, there's no such thing as going back to normal.

On Wednesday, they'll return to the same school where 17 of their classmates and teachers were gunned down . But instead of math and history lessons, their minds will be occupied by the trauma of gunfire and grief.

"I don't think I'll ever recover from this," said Daniel Bishop, a sophomore at Marjory Stoneman Douglas High School. "How am I supposed to (go back to) a place where 17 of my peers were slaughtered?"

No one knows the answer. But Daniel and many of his classmates are trying to make sure no other student will have to endure the same.

Their fight isn't over

JUST WATCHED Stoneman Douglas survivors spar with Rubio, the NRA Replay More Videos ... MUST WATCH Stoneman Douglas survivors spar with Rubio, the NRA 03:06

In the course of a week, Stoneman Douglas students went from regular teens to massacre survivors to activists rallying to ban assault weapons.

Senior Chris Grady said he remembers when outrage over the Sandy Hook massacre seemed to fade over time. He doesn't want that to happen with his school, so he's vowed to keep pushing lawmakers even after he returns to class.

"The longer we stay relevant, the more serious they're going to take us," he said.

Returning to school ... with armed deputies

Phoebe O'Mara is dreading going back to school next week. The 15-year-old freshman knew seven of the victims killed.

"I would see Gina (Montalto) in math class and Alaina (Petty) in geography class," Phoebe said.

Instead of seeing their smiling faces, she will see their empty chairs.

"It's going to be so strange not seeing them in class," Phoebe said. "It's just crazy that they're here and then they're gone. Their lives meant something. They were my friends. This is the last time this should happen."

Staff members will be allowed to return to Stoneman Douglas as early as Friday . Students and parents can return for a voluntary campus orientation on Sunday afternoon.

On Wednesday, classes will resume on a modified schedule . Students will be able to see support counselors -- as well as armed deputies on campus.

That's because Broward County Sheriff Scott Israel has ordered his deputies to start carrying rifles on school grounds

President Donald Trump suggested schools go a step further, saying teachers could be armed on school grounds . Hunter Pollack, who lost his sister Meadow in last week's massacre, supported the idea.

"It could've been a very different situation," he said. "We need more security, we need more firearms on campus, we need better background checks, and we need to study more on mental health."

But many Stoneman Douglas students, teachers and even the sheriff disagree.

"I don't believe teachers should be armed," Israel said. "I believe teachers should teach."

Looking forward to March

Senior Demitri Hoth has been one of the most vocal students fighting to ban assault weapons. He said his activism won't stop just because he'll have homework to do.

"We go back to school next week, (but) I'll definitely be speaking out still until changes are made," he said. "And hopefully be able to go to Washington on the 24th of March."

That's the day activists nationwide will gather for the March For Our Lives , an event created by Stoneman Douglas students.

Daniel said it's important to keep the momentum going.

"This is an important time for us," he said. "I really feel like this is a turning point."