(CNN) -- Students at Ohio's Chardon High School prepared to head back to class Friday for the first time since a gunman walked into the school's cafeteria and killed three teenagers.
Two other students were hospitalized and another was grazed by gunfire Monday morning.
The person who authorities say is responsible, 17-year-old T.J. Lane, was charged Thursday afternoon with three counts of aggravated murder, two of attempted aggravated murder and one of felonious assault, the latter related to an individual who was "nicked in the ear" by a bullet, according to Geauga County Prosecuting Attorney David Joyce.
Some students were with their parents in the school, situated in a community of about 5,100 people some 30 miles east of Cleveland, on Thursday and counseling has been made available at various locales since the shooting.
"I watched families walk through the school holding hands, I watched people helping each other come back into the school," said Geauga County Sheriff Dan McClelland of the scene inside the school Thursday. "It was an incredible spirit of Chardon. I'll never forget that. This is why we live here."
Friday marks the first full school day since the incident, a return that administrators and staff touted as key to helping people through the healing process.
School superintendent Joseph Bergant said that staff spent two days working on the transition, expressing confidence that they'll be ready to provide comfort and support to those still trying to make sense of this week's carnage.
Frank Hall, an assistant football coach and study hall teacher who chased the gunman from the school, said Thursday it was important that students and staff return -- if for no other reason than to show that "show that terror and evil do not win out."
"I'm here to tell you that tomorrow our schools will be open, our teachers will be there, our administration will be there, our parents and community, but more important our children will be there," said Hall.
Meanwhile, the legal process continues.
Joyce, the prosecuting attorney, filed charges against Lane around 3:40 p.m. Thursday in juvenile court. After the defendant's next court appearance next Tuesday, a March 19 hearing is scheduled that is tied to a motion to transfer his case to an adult court.
The murder charges state that the teenager "purposely and with prior calculation and design" fatally shot three people while at Chardon High.
The prosecutor has said that the sophomore confessed that he took a .22-caliber gun and a knife into the school Monday morning and fired 10 rounds as frightened students and some teachers ran for cover.
By the time the bloodshed ended, three were killed: Daniel Parmertor, 16, who died Monday; Demetrius Hewlin, 16, who died Tuesday morning; and Russell King Jr., 17, who was declared brain dead Tuesday.
This is not Lane's first brush with the law, according to juvenile records released by authorities this week.
When he was 15, Lane was charged with juvenile assault for putting his uncle in a choke hold and punching him in the face, according to an incident report from the Geauga County Sheriff's Office.
The report stated that Lane's aunt called 911 in December 2009 to report the boy and his uncle "were physically fighting" -- and, at one point, the teen teamed up with his then 16-year-old brother, who himself was later charged with simple assault. Two sheriff's deputies arrived to find the uncle "bleeding from the mouth and ... on the kitchen floor."
Lane pleaded "true," the equivalent of guilty, to lesser charges of disorderly conduct. He was sentenced to up to 30 days in a detention center, fined and ordered to complete 24 hours of community service, according to court documents.
At the time, Lane was in his grandparents' custody, according to the complaint.
Lane's driver's license was recently suspended for two and a half months after he was ticketed for "failure to control" a vehicle. The license was reinstated in early February upon his completion of a mandatory driver improvement program, records show.
Lane's friends have said that the teen had a troubled childhood.
His parents had both been charged with domestic violence against each other, according to court documents. His father also served prison time for assaulting a police officer and was charged with holding a different woman under running water and bashing her head into a wall.
"I think there's a lot of kids that go through things like that. That doesn't give them the right to kill other people," said Bob Parmertor, Daniel Parmertor's grandfather. "There are five families, including ours, that have been affected by this. No one has the right to shoot other people because they've had a rough life."
At an earlier news conference Thursday, relatives of two of the slain children described what the boys were like .
"My brother was the happiest kid on the planet," Dominic Parmertor said of Daniel. "He never got mad at anybody. He just loved to have fun. And when he was happy, other people were happy."
"He would never do anything bad to anybody," Dominic Parmertor added. "He was going to change the world. He was an amazing individual."
Phyllis Ferguson, mother of Demetrius Hewlin, said her son donated his organs. His death was "not in vain," she said. "For his one life, he gets to change eight lives."
She described her son as a "computer nerd" and "health nut" who loved football and worked out regularly.
"Most of all, I'm gonna miss his hugs and kisses," she said.
Ferguson had a message for parents: "No matter what you're going through ... you grab your children, you kiss them and tell them you love them."
Ferguson said she didn't do that on Monday, because Demetrius was running late.
Both Daniel and Demetrius were shot in the head, their relatives said.
The mother of one of the wounded children spoke as well. Holly Walczak's son Nick was wounded in his arm, neck and back, "which created a spinal shock," she said, adding that he is in serious condition but doctors are optimistic for his recovery.
If a teacher had not pulled him to a safer place, it is likely Nick would have died as well, she said.
Ron Parmertor, Daniel's uncle, called on young people to watch out for potential signs on social media that someone they know maybe troubled.
If something posted on a social network "doesn't look right, tell your mom and dad, tell the police, tell a counselor, tell a neighbor, tell a friend. Just tell somebody," he said.
And, he added, to anyone who is having trouble dealing with the tragedy: "Please talk to somebody."
CNN's Laura Dolan, Martin Savidge, Josh Levs and Kristina Sgueglia contributed to this report.