Following a storm of criticism – and at least one death threat – a California school district Monday canceled a lesson plan that instructed middle school students to make arguments denying the Holocaust happened.

The assignment, aimed at eighth-grade students in Southern California’s Rialto Unified School District, sought to teach children to learn the nature of propaganda.

“Some people claim the Holocaust is not an actual event, but instead is a propaganda tool that was used for political and monetary gain,” the assignment said, according to a document posted by The Daily Bulletin. “You will read and discuss multiple, credible articles on the issue, and write an argumentative essay, based upon cited textual evidence, in which you explain whether or not you believe this was an actual event in history, or merely a political scheme created to influence public emotion and gain wealth.”

But critics said the assignment risked misleading the 13- and 14-year-old students into believing that propaganda about the Holocaust bears factual legitimacy.

“Whatever (the district’s) motivation, it ends up elevating hate and history to the same level,” Rabbi Abraham Cooper, the associate dean of the Los Angeles-based Simon Wiesenthal Center, told FoxNews.com on Monday. “We should train our kids to have critical thinking, but the problem here is the teacher confused teaching critical thinking with common sense, because common sense dictates you don’t comingle propaganda with common truth.”

Cooper added that although teaching children about the nature of propaganda is a worthy lesson plan, the district would have been better off having children research Holocaust denial, while meeting with local survivors of the genocide.

In a statement, the district said Monday afternoon the interim superintendent will be speaking with its educational services department to “assure that any reference to Holocaust ‘not occurring’ will be stricken on any current or future argumentative research assignments.”

“The Holocaust is and should be taught in classrooms with sensitivity and profound consideration to the victims who endured the atrocities committed,” the statement reads. “We believe in the words of George Santayana, ‘Those who cannot learn from history are bound to repeat it.’”

Rialto police said one person made a number of calls to police with specific death threats directed at a district spokeswoman and the interim superintendent. Two officers were at the campus on Monday and authorities are investigating the incident.

The Holocaust, which began in 1933 and ended in 1945 with the defeat of Nazi Germany in World War II, was the mass extermination of up to 11 million people, including six million Jews, resulting in the murder of nearly two-thirds of Europe’s Jewery.

The Associated Press contributed to this report.