To clarify, this was a suicide attempt, not a mass shooting attempt. On May 17, 2019, 18-year-old student Angel Granados Dias entered Parkrose High School, Portland, Oregon wearing a black trench coat and carrying a shotgun loaded with a single shell, intending to commit suicide in front of classmates. And the teacher, Keanon Lowe, disarmed the high school student then hugged him tight.
News: https://www.washingtonpost.com/books/2022/05/12/keanon-lowe-school-nfl-interview/
The teacher, Keanon Lowe was then selected for his courageous act and was attributed with saving the lives of the students and faculty of Parkrose High School by the 'Congressional Medal of Honor Society' and awarded him the 'Citizen Honor Award'.