A high school teacher and two students sued Arkansas on Monday over the state’s ban on critical race theory and “indoctrination” in public schools, asking a federal judge to strike down the restrictions as unconstitutional.

The lawsuit by the teacher and students from Little Rock Central High School, site of the historic 1957 racial desegregation crisis, stems from the state’s decision last year that an Advanced Placement course on African American Studies would not count toward state credit.