A British school was blasted Friday after kids as young as 11 were told to shout obscenities during a lesson in swearing.

Expletives like the f-word and c-word were written on a blackboard before a teacher explained their meaning to 30 seventh graders.

S.t Laurence School in Bradford on Avon, Wilts, claims it was part of a sex and relationship education program to "dispel" the myths of swear words.

But parents say they were not consulted by head James Colquhoun about the class and say kids were left "deeply upset."

One parent said: "This is a total disgrace. Our children go to school to gain an education, not qualifications in swear words. Most kids had no idea what the words meant and were forced to grow up faster than their parents want. Heads should roll for this."

Some pupils claim the teacher told them not to tell parents about the lesson.

Deputy head Richard Clutterbuck said Friday night: "This lesson should not have focused on the slang terms. I must apologize for any distress caused."

Wilts County Council said it is the governors’ responsibility to decide specifics of sex education lessons.

In February The Sun reported on 10-year-olds at a church primary school who were told to write the crudest words they knew to "analyze bullying insults."

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