The pupil was outside school grounds in the Angered suburb at the time of the shooting. He received help from friends to make his way to the school nurse.
“The incident happened in the area around the school,” police spokesman Frans Dahlén told The Local.
Police have not made any arrests in connection with the shooting. The student was taken to Sahlgrenska Hospital to be treated for minor injuries.
“We’re questioning the pupil at the hospital,” said Dahlén.
Police sealed off the area around the school and began a forensic examination of the crime scene on Tuesday afternoon.
“He was shot with a handgun,” police investigator P-O Johansson told news agency TT.
“We don’t know what was behind it but it doesn’t seem to have been gang-related,” he added.