Police believe Samuel Paty, a 47-year-old history and geography teacher, was targeted because he showed pupils controversial cartoons of the Prophet Mohammed during a lesson on free speech.
His attacker, who's said to be an 18-year-old Chechen refugee, died after being shot by the police.
Officials say he waited outside the school and asked pupils to identify the teacher before carrying out the murder.
Kate Silverton presents BBC News reporting by Paris correspondent Lucy Williamson.
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