A primary school was forced to apologise after pupils took part in a ‘runaway slave’ PE lesson.

The gym class was organised as part of Black History Month at Madison’s Trust Elementary School in Virginia but it received a backlash from parents who felt it trivialised slavery.

The session began with a talk about the Underground Railroad – a network of secret routes and safe houses established in the US to help African-American slaves escape into free states and Canada.

The students in the third, fourth and fifth grades (ages 8-10) were then divided into groups of “slaves” and asked to overcome a physical obstacle.

The game was reportedly intended to teach teamwork, communication and cooperation.

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But Loudoun County Public Schools spokesperson Wayde Byard reportedly said that slavery was not a game and that the lesson trivialised something important.

The Washington Post reported that Michelle Thomas, president of the Loudoun chapter of the National Association for the Advancement of Coloured People (NAACP), said the parents of an African-American student told her their child said he played a runaway slave in class.

Escaped slave, abolitionist and Union spy Harriet Tubman who helped lead about 13 missions to rescue about 70 enslaved family and friends using the Underground Railroad (Chip Somodevilla/Getty Images)

She said the incident made her “feel unsafe” because she had children in Loudoun County Public Schools.

In a letter to parents, headteacher David Stewart wrote: “I extend my sincerest apology to our students and school community.

“This is contradictory to our overall goals of empathy, affirmation, and creating a culturally responsive learning environment for all.”