It would become perhaps the final act undertaken by the assistant coach and security guard, who suffered a gunshot wound and died after he was rushed into surgery, according to the school's football program and its spokeswoman, Denise Lehtio.
"He died the same way he lived -- he put himself second," Lehtio said. "He was a very kind soul, a very nice man. He died a hero."
Feis was among 17 people killed when a former student armed with a rifle opened fired on campus, unleashing a massacre that stands among the 10 deadliest mass shootings in modern US history
Colton Haab, a 17-year-old junior and football player who was close with Feis, said he heard the coach shielded three girls from gunfire.
"That's Coach Feis," Haab said, describing the educator as selfless, approachable and friendly.
"(He) made sure everyone else's needs were met before his own. He was a hard worker. He worked after school, on the weekends, mowing lawns, just helping as many people as possible," Haab said.
Haab last saw Feis Tuesday morning in a school hallway, he said. They talked "about normal stuff," like work and football.
"I'm glad he didn't suffer that much," the teenager said. "It's sad because it's not going to be the same without him at school anymore, that's for sure. Football definitely won't be the same. We're definitely going to have to band back together as brothers and mourn his loss and pick up the pieces to try to rebuild our football team."
Janitor ushers students to safety
Feis, who spent his whole career at the school after graduating from Stoneman Douglas, was among countless heroes whose stories began emerging after Wednesday's horror
Teacher Melissa Falkowski
hid 19 students in a closet as the shooting erupted. Most students communicated silently on their phones, she said. Others burst into tears.
"This is the worst nightmare that could ever happen to you," she told CNN.
Meantime, as a fire alarm blared, a janitor diverted senior David Hogg and other students away from the direction of the shooting, Hogg told CNN affiliate KTRK
. A teacher then opened a classroom door so they could hide.
"Without her, who knows how many of us would have died, 'cause we were easily 100 feet away from the freshman building," Hogg said, "and again, we thought this was a drill."