They hear about #MeToo cases in the news, and talk about them with friends.

Now U.S. students increasingly discuss the meaning of consent in the classroom.

Ten states and the District of Columbia are requiring schools to discuss what it means for a relationship or encounter to be consensual.

The trend is starting to take hold even in red states like Oklahoma, which passed a compromise bill this year that one lawmaker calls "baby steps" toward updating sex ed programs for the #MeToo era.

Critics fear such programs condone sexual activity for teens. But supporters say it's never too early for students to learn to ask a partner, "Are you OK?"