Students and staff at Skyline High school paid tribute to Carlo Tateo.
The 31-year-old physical education teacher was shot early on Sunday in San Francisco during an argument on Folsom Street.
Tateo was a father figure and a mentor for many students.
"A friend to everybody," said Brancy White, a member of the school's high school football staff. "So to lose somebody like that, the way that we did is devastating. I mean, a breath of fresh air taken out of every day."
Tateo graduated from Skyline, worked at a youth outreach group, and returned as a teacher for the past three years.
A GoFundMe page has been set up to care for his 2-year-old daughter. Click here if you'd like to help.