Angel Cruz, who turned 7 on New Year's Eve, ran into traffic lanes in the 900 block of Peach Avenue in the path of a Hyundai sedan about 3:45 p.m. Thursday, according to police and the county Medical Examiner's Office.
His mother was waiting in her parked car on the other side of the street when the westbound vehicle hit her son, who attended nearby Naranca Elementary School.
Medics took Angel to Rady Children's Hospital in San Diego, where he died shortly after 12:30 a.m.
The driver of the Hyundai, an 18-year-old man, immediately stopped and cooperated with investigators, police said. Intoxication was not believed to have been a factor in the crash.
The motorist was not expected to be cited, Lt. Rob Ransweiler said.
In a brief news conference late this morning, Cajon Valley School District Superintendent David Miyashiro asked news crews to give Angel's family and classmates privacy during their time of grief.
"The environment that our kids are in right now needs to be as normal as possible," Miyashiro said.
PREVIOUS STORY: Boy, 7, hit by car in El Cajon