7th Heaven (2001)

Simon (David Gallagher) is the sole person willing to defend a fellow classmate against an onslaught of bullies. Simon is unsure of what to do when the classmate mentions he wants to kill his tormentors.
Simon (David Gallagher) is the sole person willing to defend a fellow classmate against an onslaught of bullies. Simon is unsure of what to do when the classmate mentions he wants to kill his tormentors.
In Season 1 of the FX television horror it is revealed that deceased teen Tate Landon (Evan Peters), who is unaware of his ghostly nature, murdered fifteen people at Westfield High School in 1994. His violent massacre leaves the school librarian handicapped and leads to his own death, after being fatally shot by a SWAT team. He is unable to remember his crime but is confronted by several of his victims and ultimately finds redemption.
In this episode of the WB series, Buffy (Sarah Michelle Gellar) develops mind reading abilities. While in the school cafeteria, she hears the thoughts of an ignored student who threatens to kill everyone in the school. The WB had to postpone airing an episode due to the Columbine High School shooting that took place a week prior to the originally scheduled air date. The episode, “Earshot,” was not aired until September, five months after it was supposed to premiere.
In 1995, two teenage boys (Kyle Gallner and Will Rothhaar) videotape themselves going on a shooting spree at a local mall, after which the two young men commit suicide. The Cold Case team is prompted to reinvestigate the case when new evidence suggests that there may have been a third shooter who got away.
In a 2011 episode of Criminal Minds, alumni return to North Valley High School in order to commemorate the ten-year anniversary of a school shooting and bombing committed by well-liked but narcissistic student. As several of the survivors return, a copycat killer seems to be on the loose. One of the suspects is Randy’s sweet but impressionable little brother, who was seven at the time of the original shooting.
An arrogant high-school football star, known to be an abrasive class clown and a bully, is found murdered in a school bathroom. The CSI team soon realizes that there are a lot of suspects, as their victim bullied many of his fellow students.
After being humiliated by a mean-spirited prank, Degrassi High School student Rick (Ephraim Ellis) brings a gun to school, threatening the entire student body. Rick paralyzes fellow classmate and friend, Jimmy (Drake), when he shoots the teenager in the back. Rick is killed during a physical struggle with another student, when the gun accidently discharges.
After gunshots are heard during a glee rehearsal, the students and teachers are trapped in the choir room, where the aspiring singer-songwriters film messages to their loved one. At the end of the episode, cheerleading coach Sue Sylvester (Jane Lynch) claims responsibility, and is subsequently fired from McKinley. It is later revealed that the gun really belonged to teenager Becky Jackson (Lauren Potter), who has Down syndrome and was frightened about her impending graduation. The episode aired four months after the Sand Hook Elementary School shootings, leading one Sandy Hook parent to complain that it was still "too soon."
A school shooting in which four are killed and 12 are wounded, prompt an investigation headed by Detectives Briscoe (Jerry Orbach) and Green (Jesse L. Martin). It soon becomes apparent that more than one child fits the profile of a youth capable of committing such violence.
A gun is heard being fired in the hallway of Angela’s (Claire Danes) high school, and, though no one is hurt, numerous rumors begin to circulate about the possible shooter. The gun ends up belonging to Angela’s openly gay friend Rickie (Wilson Cruz), who brought the gun to school as a means of protection.
The NCIS team must apprehend the teenage son of a Marine Major, who arrived at school with a bomb strapped to his body. He takes his classroom hostage with one simple demand: bring his mother to the classroom before sunset. The team discovers that his mother is dead, having drowned in a boating accident the year before. In another unfortunate turn of events, Gibbs (Mark Harmon) attempts to infiltrate the school but ends up becoming a hostage himself.
After a school shooting, one of the shooters is found among the dead but his accomplices are unaccounted for. After learning that the dead shooter belonged to a nerdy outcast group of online gamers, the team finds a second suspect at a cybercafé, where he is killed trying to escape. Charlie (David Crumholtz) uses the school's radio frequency identification system to uncover a third accomplice, a student journalist, who was using the nerds so she could target the athletes who raped her at a party months ago.
In Season 3 of the teen melodrama, a bullied student, Jimmy, takes the students of Tree Hill High School hostage. He is talked into letting his two hostages go by fellow student Keith, Jimmy agrees but, after letting the kids go, kills himself. The show takes the dramatics even farther by having another student kill Keith with Jimmy's gun, thus posthumously framing Jimmy with the murder.