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.”