Other recent shootings at schools

Text is about shootings at schools from 1997 till 2001 year in USA.
Shootings at schools were made by adolescences who were from 6 to 19 years old. Some of the victim's were shot dead, other were wounded. Young children commit cruel crimes for some reasons. One criminals are mentally ill, want to revenge for a person, other have easy access to the gun. Some of the offenders were sentenced to life imprisonment, other should spend just few years in prison, one 6 year old boy was not charged because of his age.
In conclusion, it can be stated: some juveniles are mentally unstable, can not control their actions and do not understand consequences.