PARKLAND, Fla. — Students at Marjory Stoneman Douglas High and other schools across the U.S. bowed their heads in a moment of silence and took part in volunteer projects Thursday to mark the first anniversary of the shooting rampage that claimed 17 lives. But for many Parkland students, the tragedy was still so raw they couldn’t bring themselves to set foot in the building.

Fewer than 300 of the 3,200 students at the high school showed up for what was only a half-day, with classes cut short so that the teenagers would not be there around 2:20 p.m., the traumatic moment when gunfire erupted last year.

Senior Spencer Bloom skipped school to spend the day with students from the history class he was in during the shooting. He said he struggles with panic attacks and feared he might have one if he went to school.

“There’s all this emotion and it’s all being concentrated back on one day,” Bloom said.

The massacre on Feb. 14, 2018 – Valentine’s Day – inflamed the nation’s debate over guns, turned some Parkland students into political activists and gave rise to some of the biggest youth demonstrations since the Vietnam era.

Many Stoneman Douglas students arrived wearing the burgundy #MSDStrong T-shirts that have become an emblem of the tragedy. Outside, clear plastic figurines of angels were erected for each of the 14 students and three staff members killed. A moment of silence was observed there and at other schools across Florida and beyond at 10:17 a.m., a time selected to denote the 17 slain.

Reporters were not allowed inside the school, but students packed lunches for poor children in Haiti as part of a number of volunteer projects undertaken to try to make something good come out of the tragedy.

Grief counselors and therapy dogs were made available along with massages and pedicures. An interfaith service occurred later in the day at a nearby park.

Freshman Jayden Jaus, 14, said the moment of silence was “a bit emotional and a little intense” as the principal read the victims’ names over the public address system.

Sophomore Julia Brighton, who suffered nightmares for months after the gunman killed three people in her classroom, placed flowers at the memorial outdoors instead of going inside and “putting myself through that.”

Victims’ families said they would spend the day quietly, visiting their loved ones’ graves or participating in low-key events like a community walk.

Lori Alhadeff posted an open letter to her 14-year-old daughter Alyssa, who died in the shooting. Alhadeff remembered how Alyssa didn’t want to go to school because she didn’t have a valentine. But when she dropped her daughter off, she put a pair of diamond earrings in Alyssa’s ears and gave her a chocolate bar to make her smile.

They told each other, “I love you,” and Alhadeff watched Alyssa walk away in a black and white dress and white sneakers: “Your long, dark hair dangled. Your makeup looked just right.”

“The last time I saw you alive,” wrote Alhadeff, who was elected to the Broward County school board after the shooting on a platform pushing campus safety.

More than a thousand people gathered in the evening at Pine Trails Park, about a mile from the school, for an interfaith service that opened with a video highlighting dozens of service projects launched in honor of the victims.

The former student accused of opening fire with an AR-15 assault rifle in the Parkland attack, Nikolas Cruz, now 20, is awaiting trial.