Administrators with Littleton Public Schools responded to allegations they missed the warning signs that could have prevented the deadly 2013 shooting at Arapahoe High school.
Thursday night, dozens of parents packed a meeting to hear the key findings of the report.
Superintendent Brian Ewert also spoke for the first time since the report was released.
He said there are many things that could have been done differently to prevent this tragedy.
Parents said the healing now needs to begin.
Ewert said every school has a school resource officer now, and they will make more changes as they take in the findings of the report.