Keep grown-ups’ pronoun fights out of grade school classrooms

In the 1990 movie “Kindergarten Cop,” it is a five-year-old boy, not Arnold Schwarzenegger, who blurts out the actual biology lesson: “Boys have a penis, girls have a vagina.” Schwarzenegger’s character, an undercover detective drafted into substitute teaching, doesn’t linger on the matter or turn it into a discussion. Rather, he offers a dry, one-line…