It's a short story so if I give you a longer summary then you'll know everything that happens so just read it.

   It’s March 30th, the day before spring break. Jennifer Clark sits in class, pretending to read a book with a slight grin on her face as she thinks about what she’s gonna do this spring break. About 15 students haven’t finished the quiz. Jennifer and a few others are just counting the minutes ‘till the end of the period. The teacher sits at his desk putting grades into the computer. The classroom is silent. Jennifer thinks she hears a noise outside, it’s the fire alarm. Right as everyone starts to pack up, the classroom door opens. Two men enter the classroom dressed in black with masks, each carrying a short-barreled automatic rifle. One takes out the teacher directly while the other opens fire at the students. Jennifer ducks in time and lies still on the floor. All the other students are dead. Jennifer lies in horror as she tries to watch the gunmen without getting shot. The taller gunman takes off her mask while the other checks to see if everyone is dead. Jennifer recognizes the unmasked gunman and can’t help but to react.
      “Lauren?” Jennifer blurts out. Lauren, shocked, looks down at Jennifer on the floor. The still-masked gunman turns and points his weapon at Jennifer, who flinches in terror.
      “Don’t shoot, don’t shoot” Lauren urges the masked man, who lowers his weapon. Lauren collects herself “Holy s***, good instincts Jennifer. I thought you hit everyone, Ethan?” Lauren questions.
      Ethan removes his mask, “I thought I did” he responds. “We’re wasting time. Take her out and let’s go!”
      “No, Ethan, it’s not her turn to die” Lauren remarks. Then she points the gun at Ethan and shoots him in the head.
      Jennifer is about to scream, until Lauren points the gun at her. “Quiet or I shoot” Lauren threatens.
      “Please, Lauren, let me go. We’ve been friends for years. I won’t say anything, just please let me live” Jennifer pleads as she is covered in the blood of Ethan.
     “No, no, no ,no” Lauren says as she smiles, shakes head, eyes closed. “I can’t let you go.”
     “Why me? What do you want from me?” Jennifer asks, while crying.
     “This isn’t about you” Lauren retorts. “This is for every student in this country who is forced to live in fear because of people like Ethan.”
     “What, what are you talking about?” Jennifer questions, sobbing.
     “Day after day, kids are being killed in their classrooms. How many shootings will it take for this country to wake up?” Lauren asks.
     “So you go shoot up a school?” Jennifer blurts out in confusion.
     “Whatever it takes” Lauren says sinisterly.
     “You’re insane! Ethan thought this too?” Jennifer asks.
     “Ethan, the perfect target” Lauren looks down at his body. “Look at him. I wasn’t surprised when he told me he already had a plan to shoot up the school. I just helped him out. He didn’t have the money, so I bought him a gun. That’s not gonna stop everyone from believing he shot everyone and then killed himself.”
     “You think you’re gonna get away with this?” Jennifer asks.
     “Doesn’t matter. This isn’t about me” Lauren says softly.
     “Just please let me go” Jennifer pleads.
     “I have something better for you. I’ll make you a martyr” Lauren says as she points the gun at Jennifer.
     “Wait no-“ Jennifer shouts as she gets cut off by the bullet.
     The room falls silent as Lauren lowers her weapon. The floor is covered with blood. She re-collects herself as she takes off her backpack and puts the gun inside. She continues to remove her black clothes until she’s just wearing a T-shirt and jeans. The window allows her to see her reflection as she fixes her hair. Almost the entire student body is gathered outside the school on the grass. Lauren picks up her backpack, walks until she finds a side exit where a few stragglers are headed out. Nobody knows about the shooting yet, it appears. Lauren joins the rest of the students in grass outside, completely unnoticed. Inside her backpack, an automatic rifle. Whispers start to circle around the students that there was a shooting. They say it’s a suicide. Lauren stands surrounded by students, with a slight grin on her face as she thinks about what she’s gonna do this spring break.