A high school teacher in Iowa in the US has been put "on leave" after asking students to "pretend you are a black slave" for a school assignment.
The teacher, whose name was not released, assigned the Iowa City school district online learning programme to different schools, which has since been removed, Iowa City Press-Citizen reported.
The teacher asked students to write four sentences about what they would do if they were a slave who was freed.
"Think very, very carefully about what your life would be like as a slave in 1865," the assignment instructed.