The student, who has not been identified because of his age, told police it went off accidentally when he reached inside to get food on Tuesday. The gun accidentally discharged, hitting a 15-year-old boy in the neck and a 15-year-old girl in the head.
The boy is OK, but the girl remains listed in critical condition. Doctors said her condition is improving. She could even go home in a matter of days.
The 15-year-old boy's family retained lawyers from the Cochran Firm on Friday. They plan to file a claim against the LAUSD for failing to protect students with daily random weapons searches.
Prosecutors want the teen tried as an adult. If that happens, he could face as many as seven years in state prison.
Police said the suspect got the gun from his stepfather without his stepfather's knowledge.
Investigators said two more students have been arrested in connection with the shooting, accused of helping the suspect hide and get rid of evidence.
Many students at Gardena High School said they knew the suspect had a gun, but they didn't want to be a "snitch."
Police said people who want to report a weapon or any contraband can call a tip line at (800) 954-4357. Callers can remain anonymous.
The teen's next court appearance is scheduled for Feb. 18, when a date will be set for a hearing to determine if he will be tried as a juvenile or an adult.