SOUTH ORANGE, N.J.—Posters by New Jersey fifth-graders that advertised slave auctions have been removed from the wall of an elementary school hallway after some parents questioned the assignment.

The South Orange School District is planning a community meeting to discuss whether the assignment is appropriate for students of that age, NJ.com reported.

Superintendent John Ramos said in a note to parents that the project at South Mountain Elementary School is part of a larger colonial America unit that’s been used for 10 years. He said an anti-bias expert consulted by the district after parents raised concerns highlighted the fact that schools often skip over painful aspects of American history, and he said educators need to do a better job of “acknowledging the uglier parts of our past, so that children learn the full story.”

One poster listed the names of available slaves, who included 12-year-old Anne, described as “a fine housegirl.” Another poster says, “All slaves raised on the plantation of John Carter,” and specifies that only cash is accepted.

Ramos says the projects should have been accompanied by an explanation. He said that some families have supported the assignment “because they see it as an important opportunity to examine this shameful and too often ignored chapter of American history,” while others were disturbed that young students “were being asked to put themselves in the virtual shoes of people who subjugated others.”

The district says it hasn’t decided yet whether the assignment will remain part of the curriculum next year.