Kaylub Giamanco has been hailed as a hero for killing a teenager who fatally shot three children and a teacher.
The teacher said she could not help children because she was badly injured by the attacker.
The 16-year-old suspect previously attended the primary school and had targeted a special educational needs classroom, police say.
Investigators say the 31-year-old California man wanted to kill as many high-level officials as possible.
The gunman showed no remorse and grumbled about an injury he sustained in the attacks, said investigators.
Brown University student Mia Tretta describes her emotional response at surviving a mass shooting on her college campus, having experienced gun violence in school as a child.
Abigail Zwerner sued a school administrator, claiming they had ignored a warning about the gun.
Taki Allen, 16, said he was eating a bag of Doritos after football practice before being handcuffed by police.
The Trump administration wants the law upheld after a Texas man challenged a gun charge.
