Boy shot at elementary school died by Ashley Mendoza

During a South Carolina shooting, young Jacob Hall was shot and later died in the hospital. The suspect of the shooting is under police custody.
I can't understand why people believe that shooting up a school is something they should do, it's stupid.
  
http://www.cnn.com/2016/10/01/us/south-carolina-elementary-school-shooting-victim/index.html