How important is it that violent, regretful events in America's history are taught in American schools? Is what the author says about school children not getting the full story of the past still true today in some cases?

Schools are not adequately teaching the history of hard history like American slavery, educators are not sufficiently prepared to teach it, textbooks do not have enough material about it, and – as a result – students lack a basic knowledge of the important role it played in shaping the United States and the impact it continues to have on race relations in America.

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