SWAMPSCOTT – A mother and her two middle school-aged children were struck by a car Tuesday night on Essex Street outside Swampscott High School and hospitalized, police said.School Superintendent Matthew Malone said a Swampscott Middle School band and chorus show had just ended when the family was hit by a late-model Honda Civic at about 7:30 p.m. He confirmed the two children are students of the middle school.Police said a 12-year-old girl was most seriously injured. An 8-year-old boy and the mother were less seriously hurt. All of the injuries were described as non life-threatening.Police did not release the victims’ names Tuesday night.Mike Hartmann of Swampscott said he was about five cars behind the driver who struck the family and initially thought the accident was a fender bender.”A lot of people gathered around them,” he said. “The only one I was concerned about was the one girl on the ground.”Both lanes of Essex Street were closed for about 30 minutes after the accident, then only one lane was reopened. The driver stayed at the scene with police after the crash.In addition to the middle school show, a high school girls basketball game against Gloucester was taking place inside the high school when the accident occurred.The family appeared to have gotten struck in the northbound lane approximately 75 yards before the crosswalk at the traffic light in front of the high school. It’s about the same location where a high school student was struck by a car last year.”It is a bad street,” said Malone, who was at the accident scene. “The lighting on the street is challenging? We have to keep encouraging kids and parents that you’ve got to keep crossing in the crosswalks, especially when it’s dark.”It was unknown Tuesday night if the driver would face any charges.