PARKLAND, Fla. >> Students and teachers returned today to Marjory Stoneman Douglas High School for the first time since a troubled teenager with an assault rifle killed 17 people there and thrust the Florida school into the center of a renewed national gun debate.

Students and staff cried and hugged each other during shortened classes that lasted a half-day.

On the way in, teens were guarded by dozens of police officers. The officers were accompanied by comfort animals, including dogs, horses and a donkey. One of the horses had “eagle pride” painted on its side. A nearby woman held a sign offering “free kisses.”

After school dismissed, members of the Guardian Angels wearing their trademark red berets lined the streets at a crosswalk.

“In the beginning, everyone was super serious, but then everyone cheered up and it started being the same vibes we had before the shooting. People started laughing and joking around,” said Kyle Kashuv, a junior who said he hugged every single teacher.

He was amazed by the outpouring of support from the community including the police presence, animals and well-wishers. There were letters from all over the world and “banners on every single wall,” he said.

Seeing officers carrying military-style rifles rattled some students.

“This is a picture of education in fear in this country. The NRA wants more people just like this, with that exact firearm, to scare more people and sell more guns,” said David Hogg, who has become a leading voice in the students’ movement to restrict assault weapons.

Grief counselors were on campus “to provide a lot of love, a lot of understanding” and help students “ease back” into their school routines, Broward Schools Superintendent Robert Runcie said.

The freshman building where the massacre took place remained cordoned off.

Principal Ty Thomas tweeted that “our focus is on emotional readiness and comfort, not curriculum: so there is no need for backpacks.”

The class schedule began with fourth period, so teachers and students could first be with the people they were with during the shooting.

“It’s not how you go down. It’s how you get back up,” said Casey Sherman, a 17-year-old junior. She said she was up late working on preparations for the March 14 national school walkout against gun violence, and not afraid to be return, “just nervous.”

Then she saw all the officers.

“Oh, wow, there are a lot of police,” she said as she pulled up to the entrance. “Oh my goodness, yeah, that is a lot.”

Many students said the debate over new gun laws has helped them process the traumatic event and prepared them to return.

Alexis Grogan, a 15-year-old sophomore, was concerned that it might be too soon to go on as usual without slain friends such as Luke Hoyer, who sat two seats behind her in Spanish class. But the students’ effort to strengthen gun laws has buoyed her spirits.

“I am so proud of how the kids at my school have been fighting because we all want change to happen and, as we see the progression, it really shows us that people do care. And they do hear what we have to say,” Grogan said in a text message.

As students went back to class, Dick’s Sporting Goods, a major U.S. retailer, announced that it would immediately halt sales of assault-style rifles and high-capacity magazines at all of its stores and ban the sale of all guns to anyone under 21.

On Tuesday, victims’ relatives kept up the pressure in Florida’s capital, offering emotional testimony before a House committee that voted in favor of a bill to raise the minimum age to buy long guns from 18 to 21 and to create a program allowing teachers to carry concealed weapons in classrooms if their school district allows it. Those teachers would receive law-enforcement training and get deputized by the local sheriff’s office.

State lawmakers continued their investigation of how the suspected shooter, Nikolas Cruz, managed to slip through local law enforcement despite previous warning signs.

The Florida House voted today to subpoena records from Broward County and the school board, as well as sheriff’s offices in Broward and Palm Beach counties and the city of Coral Springs. The subpoenas demand that the records be turned over by Tuesday.

Florida Gov. Rick Scott said he hopes a gun and school-safety bill is passed before the annual legislative session ends March 9. The measures he proposed did not include arming teachers, but he declined to say Tuesday whether he would veto a sweeping package that includes that provision.

The Broward superintendent has spoken out firmly against the idea of arming teachers.

Marion Hammer, a lobbyist for the National Rifle Association and Unified Sportsmen of Florida, said she supports school security and keeping guns out of the hands of the mentally ill, but “guns are not the problem.”

Kyle Kashuv said he was most moved by a tattoo his teacher got that said “MSD Strong” with a giant eagle.

“The shooting doesn’t define us,” Kashuv said. “We’re really moving past it and trying to heal right now.”