Another has serious injuries and two victims are in a stable condition in Starship Children's Hospital. A fifth pupil was treated at the scene but did not need to go to hospital.
Paramedics are shown giving vital first aid to two badly injured children lying where they were flung on the asphalt.
One can be heard moaning in pain above the sound of car engines slowly filing past the carnage.
Those mowed down were left spread over many metres with one boy using a backpack as a makeshift pillow while paramedics assess his injuries.
School pupils are shown comforting each other in the midst of the shocking ordeal while other adults retrieve school gear.
Passing motorists have described the horrifying sight of the injured teenagers left skittled by the car.
North Shore resident Anna Grygorenko was caught in traffic on her way to work when she drove into the rush-hour nightmare about 8.30am.
Grygorenko said as she wound down her window sounds of wailing soared over idling engines.
"There were lots of people and debris on the side of the road.
"I saw lots of kids in school uniform on the ground.
"I was driving past at the time and it must have just happened as no paramedics or police were on the scene yet.
"I lowered my window to listen for ambulance siren but instead I heard wailing from the victims," she said.
One girl was lying motionless across the road.
Vehicles were parked around the crash scene, apparently protecting the students from further harm.
Local business owner Lance Shepherd said it looked like the Nissan Skyline had mounted the footpath about 50m before the bus stop and crashed through six steel panels of a barrier fence.
He said an injured girl was left lying with her head in the gutter. He could see a shoe on the ground, a school bag and text books in the bus shelter.
Wairau Rd remains cordoned off around the crash scene while the Serious Crash Unit investigates.
Waitemata Police acting Inspector Jason Homan said the driver of the car was not injured.
Police and Victim Support were working closely with the families of the students and the school to support them.
