The victims, Mark McCullum, 14, and Caroline Sinderby, 15, died when the car, a BMW, somersaulted into a field after crashing into another car at 91mph, Maidstone Crown Court was told.
Alan Thompsett, 19, from High Street, Blue Town, Sheerness, Kent, was accused of killing them both by dangerous driving on the Isle of Sheppey. He admitted the charge at a previous hearing and had been remanded in custody while reports were compiled.
Thompsett had also admitted handling the stolen car, three burglaries and stealing another car.
He received a 3 1/2 -year sentence for each death, and 12 months for handling the car, all to run concurrently. He also received three concurrent six month sentences for each burglary, which were added to the previous sentences.
He received an additional custodial sentence of three months for another burglary committed after he escaped from a probation centre, to run consecutively to the other terms. He was also banned from driving for five years.
The court was told by Michael O'Sullivan, for the prosecution, that Thompsett had stolen the BMW in Herne Bay on 17 July.
After smoking several joints of cannabis, he turned up at a fairground at Sheerness, the Isle of Sheppey, and invited some young people to join him.
'It was clear he didn't have a great deal of ability to drive the car,' Mr O'Sullivan said. 'He crashed the gears, stalled the engine, overtook cars on the wrong side of the road, drove very fast and then braked very hard. Heading towards Leysdown he increased speed, tyres screeched as he turned corners. One of the passengers noted the speedometer touching 110mph.
'A Mr Cairns who, with his wife and four children was driving in the opposite direction, saw the BMW coming towards him on the wrong side of the road at excessive speed. It was clear to him the driver had lost control of the car which crossed the centre white line three times.'
The BMW swerved and hit Mr Cairns's car on the side, swung to the near side, and crashed into a field, landing on its roof. Mark and Caroline were killed, and another passenger, Clare Abbott, suffered severe injuries. Some of the Cairns family were hurt, but not seriously. Thompsett escaped with minor injuries.
Blood samples were taken from Thompsett, and showed traces of cannabis. He admitted smoking five joints that day. He told police: 'It was the drugs, you know.'
Sentencing him, Judge Felix Waley said: 'You killed two young people and you killed them driving at speeds of over 100mph.
'You were incompetent as a driver and had no licence. You were at the time affected by drugs and it's a miracle you did not kill more people.'