The boy, identified only as Carlos, told reporters at a news conference that he remained calm during the ordeal because his mother used to make him practice dialing 911 in case of emergencies.
How did his mother say he did?
"Excellent!" the second grader said.
Carlos, sporting a Los Angeles County Sheriff's Dept. baseball cap, gave a hug to dispatcher Monique Patino, who called the boy "my little hero."
"I said he was very brave and I'm very proud of what he did," Patino said, occasionally dabbing tears from her cheek.
The assailants held the parents at gunpoint Tuesday while the boy and his 6-year-old sister hid in a bathroom. Carlos told Patino breathlessly that there was "some guy who's going to kill my mom and dad" and begged authorities to "bring cops. A lot of them! ... And bring soldiers, too."
About 90 seconds into the call, his sister starts screaming as someone apparently breaks into the bathroom. The line stays connected, and a distraught-sounding Patino can be heard telling colleagues what she'd heard.
"Just hearing them scream and crying for help, I just felt their fear through the phone," said Patino, herself a mother of 7- and 8-year-old children.
Carlos said there were three assailants and two of them had guns.
"I'm still astounded by his mindset," Los Angeles County Sheriff's Sgt. Douglas Jensen said. "To be able to think about getting his sister, grabbing his phone, locking himself in a bathroom and calling 911. It shows so much."
Detectives were trying to determine the motive for the break-in. Capt. Patrick Maxwell said the 6-year-old girl had left the front door open after running to the family's car to grab her lunch box. The assailants burst in soon after.
"We don't know if it was random, we don't know if it was targeted," Maxwell said.
In the 911 call, Carlos sounds frightened but keeps his composure and explains what is happening.
"Come really fast, please, please," he said. "They come, they ring the door and they have guns."
At the news conference, Patino said she was emotionally affected by the call, especially not immediately knowing what the outcome was.
"I had to take a walk and shake it off a little bit," she said.
Deputies were on scene within three minutes, but the assailants had escaped in a green or gray two-door compact car, Jensen said.
"When one of the cops cars came, they just ran," Carlos told reporters.