Stop having extracurricular activities, if that is the price for not giving into sexual perversion. Make a no romantic or sexual contact rule for everyone while on school property.
“Make a no romantic or sexual contact rule for everyone while on school property.”
That is the only way around this issue as a school cannot make a rule saying that two girls cannot kiss or hold hands in the hallway while permitting a boy and a girl to hold hands or kiss in the hallway.
Furthermore, the district screwed-up by admitting that a prom was a school sponsored sexualized event where only a certain class of students could participate.
The school district had no chance in a courtroom.