Chantelle Keywood was killed along with her 22-month-old sister Yleina in the collision on the B6042 near Creswell, Derbyshire, on Monday afternoon.
The Year 1 pupil, who attended the Priory Church of England Primary School in Worksop, was described as a “quiet, thoughtful and sensitive” girl.
In a statement released by the Diocese of Southwell and Nottingham, a spokesman for the school said: “Our thoughts and prayers are with the whole Keywood family and those close to them.”
The girls’ 29-year-old mother and their seven-year-old sister, who have not been named, were treated in hospital after a Peugeot 106 collided with a Citroen C2 at about 4.45pm on Monday.
The driver of the Citroen, a 23-year-old woman from Worksop, sustained an arm injury.