Kendrick Castillo was three days away from graduating from STEM School Highlands Ranch when a fellow student barged into his British literature class and pulled out a gun from a guitar case.



“Don’t you move,” a student recounted the gunman saying as “The Princess Bride” played on the television.



Castillo, 18, and two of his classmates defied the orders and launched at the attacker, giving their fellow students extra seconds to find cover. Castillo took a bullet to the chest while trying to subdue the gunman.



He was the only one killed in the attack last Tuesday afternoon, but eight others — all students — were injured as well. And yet another school was left to grapple with yet another tragedy.



According to a New York Times’ analysis, the attack was the fourth school shooting in the Denver area and at least the 111th in the United States since 1970. All told, 202 people have been killed and 454...