It’s Black History Month. Let’s talk about it.

It’s Black History Month in America. But this year, teachers who talk about that history may fear their lessons could get them fired or funding for their school cut — because in states across the country, lawmakers are passing educational gag orders to restrict what teachers can say and teach in the classroom about race.

Historian Carter G. Woodson began Black History Month nearly 100 years ago as “Negro History Week.” This annual February celebration of African-American history and experience has been a staple in schools across the United States since the 1970s.

Now, the honest history of race, slavery, the Jim Crow period, and even the civil rights movement have come under attack through legislative restrictions on the freedom to read, learn and teach at both the K-12 and college levels. Ten states have already passed such bills, and more could soon follow. More than 150 professional organizations have condemned gag orders as representing “a white-washed view of history,” but legislatures, driven by political calculations, continue to introduce and pass the bills.

As tracked by PEN America, educational gag orders are currently under consideration in 29 states. That includes Virginia, where Woodson was born in 1875; Kentucky, where he attended college; and Illinois, where, in 1915, he and other Black historians founded what is now the Association for the Study of African American Life and History. It includes West Virginia and North Carolina, two of the first three states to adopt “Negro History Week” in 1926 as part of their school curricula. It includes Ohio, where Kent State University first designated the entire month of February as Black History Month. It includes Michigan, the home state of President Gerald Ford, who issued in 1976 the first presidential proclamation honoring Black History Month.

Promoting the first “Negro History Week” in 1926, Woodson was clear-eyed about the purpose of teaching Black history. The widespread lynching of African-Americans by white mobs, he wrote, stemmed from “education and practice” suggesting that “the Negro is nothing, has never been anything, and never will be anything but a menace to civilization.” To “bring about a reign of brotherhood” required “thorough instruction in the equality of races.” “Dividing prejudices” could be destroyed by “truth.”

The current onslaught of educational gag order bills, however, would outlaw some of the honest and accurate classroom history he envisioned. Oklahoma’s HB 2988 would ban teaching “that America has more culpability, in general, than other nations for the institution of slavery” or “that America, in general, had slavery more extensively and for a later period of time than other nations.” The bill, wrote the American Historical Association, “would discourage instructors from teaching students that ... the Plessy v. Ferguson decision legalized racial segregation” or that “the overwhelming majority of slave holders in the U.S. identified as white.”

Elsewhere, Mississippi’s HB 437 would ban mentioning the idea that “the State of Mississippi is fundamentally, institutionally or systemically racist.” Missouri’s HB 2189 would mandate that classroom materials “promote an overall positive…history and understanding of the United States.” New Hampshire’s HB 1255 would ban “promoting a negative account or representation of the founding and history of the United States ... which does not include the worldwide context of now outdated and discouraged practices.” Michigan’s SB 460 would make it illegal even to mention the idea that “certain races are fundamentally ... oppressed.”

It’s not just state legislatures; it’s local school boards. Last year, a board in Tennessee and Pennsylvania considered banning from school libraries the book “Hidden Figures,” about three Black women mathematicians who helped NASA win the space race, and the autobiography of Ruby Bridges, the first Black child to attend an all-white New Orleans public school. Martin Luther King, Jr.’s daughter Bernice had to speak out to prevent a district from banning a biography of her father.

Many aspects of the history of race and slavery in the United States are hotly contested, even among historians. Topics such as the role of slavery in the American Revolution require some room for debate, as do specific questions about the degree to which racial injustice remains entrenched in American institutions. These sweeping bans shut down those conversations. Some would make it illegal for teachers to assign Woodson’s own books.

“Race prejudice,” Woodson wrote in 1926, “is not something inherent in human nature. It is merely the logical result of ... thorough education in the belief in the inequality of races.” If we persist in letting politicians limit an honest retelling of America’s history of racism and close off space for open conversation, we will succeed only in inculcating prejudice in a new generation of Americans.

Young is senior manager, free expression and education at PEN America, where he recently co-authored an update on gag orders in higher education. He is the author of “The Age of Charisma: Leaders, Followers, and Emotions in American Society, 1870-1940.”