This is a teen movie plotline playing out in real life.
It's Footloose by way of Mean Girls principal Mr. Duvall: Mount Anthony Union High School principal Sue Maguire canceled the school's upcoming homecoming dance because she is sick of seeing so much of a certain "highly sexualized form of dancing," aka twerking, aka thanks, 2013 Miley Cyrus!
In a letter to the editor of the local Vermont paper, Maguire explains, in part, "Over the past couple of years, since Miley Cyrus took the stage 'twerking' at the 2013 MTV Video Music Awards, our students' dancing behavior has crossed the line of what we can condone as appropriate behavior at a school. Twerking is dancing to popular music in a sexually provocative manner involving a low squatting stance and thrusting movements. Students do not face one another or remain with the same person for the length of the song. If you haven't seen twerking, I would encourage you to research this online."
Why, back in Maguire's day, teens waited until after dances to go hook up in the parking lot. (To be fair to Maguire, her letter also outlines some problems with consent between students for various types of dancing.)
Never fear, hormone-addled teens of Mount Anthony Union High School: If teen movies have taught me anything, it's that one fun-sucking principal rarely is able to shut anything down for long. I would encourage them to reserach this online.