Tenth-graders at a Missouri high school last week had to watch a slideshow on “oppression and privilege” that appears to violate state law by using information from a Planned Parenthood affiliate that lists abortion clinics on its website. The website of the Planned Parenthood affiliate tells teens about “porn literacy” and “hookups” for casual sex. The class of sophomores at Webster Groves High School near St. Louis watched a slideshow titled “Being an Ally,” which lists so-called oppression categories as “racial,” “class,” “gender,” “sexual orientation,” “religion,” and “immigration status.” “It’s wrong to teach that different categories of human beings are...