By Lucy Osborne An A-level pupil expected to achieve top grades at Margaret Thatcher’s old school was killed on her way to class when her friend drove into a lorry. Emily Challen, 17, died almost instantly when the car she was in ploughed into the back of the stationary HGV at 40mph. Driver Aimee Culpin failed to see it because she had been looking over her right shoulder at the traffic, a court heard yesterday. Miss Challen – who was head of her house at Kesteven and  Grantham Girls’ School – was in the front passenger seat when she died just four days before her 18th birthday on February 15 last year.
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Emily Challen, 17, died almost instantly after the crash on the A1
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Driver Aimee Culpin did not see HGV while driving at 40mph, court heard
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Miss Challen was head of house at Kesteven and Grantham Girl's School
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Culpin, 19, broke down in tears after admitting death by dangerous driving
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Judge at Lincoln Magistrates' said the case was 'awful' and 'tragic'
‘I could not and still cannot understand how @placeholder could have got her car into this position, causing the death of my daughter.