Police say the victims were all students walking home from Los Alamitos High School when the crimes happened Thursday afternoon.
Investigators say two men approached a 15-year-old boy about a half-mile from school. Police say one of the suspects motioned as though he had a gun in his jacket as he forced the first victim to hand over his cellphone and other items.
The suspects then demanded the cellphone from a 15-year-old girl who witnessed the first robbery.
Police believe that less than a half-hour later, about a mile away, the same two men robbed another boy.
"Same thing. He had his iPod or some type of electronic device stolen from him," said Los Alamitos Police Sgt. Richard DeLeon.
Investigators say another 15-year-old girl who was with that boy was shoved by one suspect up against a car and assaulted.
"He inappropriately touched her body with his hands," said DeLeon.
Police say they've increased patrols in the area and school officials have notified parents of the incidents.
Police describe one suspect as a black male in his 20s with a medium build, standing between 5 feet 7 inches and 5 feet 10 inches tall. He has a tattoo on his neck and was wearing an earring. He also has a goatee.
The second suspect is described as a black male in his 20s standing 6 feet 1 inch tall with a thin build. He has short hair and was wearing a dark shirt and dark jeans.
A dark, older-model Kia or Hyundai sedan may be involved. It was seen near one of the robberies. That driver was described as a heavyset woman.
If you have information related to the case, contact the Los Alamitos Police Dept. at (562) 431-2255 ext. 405.