Thousands of teachers are pledging to teach critical race theory in the face of state laws seeking to ban it from classrooms. More than 5,000 educators have signed the Zinn Education Project’s "Pledge to Teach the Truth" since June 21. In the letter, the leftist education group claims the United States was founded on "structural racism and oppression"—tenets of the Marxist-based ideology called critical race theory. "We, the undersigned educators, refuse to lie to young people about U.S. history and current events—regardless of the law," the pledge reads. Legislatures in several states have passed bills to restrict educators from teaching...