The cis kid who was cast to replace the trans kid should refuse on principle.
The whole cast and backstage staff should pretend to go along with it until opening night, and then on opening night as the curtains open, they make a short statement about the injustice then walk off stage and go home.
Alternatively, the cast should covertly learn the role of an opposite gender cast member. Then on opening night, the cast members assume their opposite role and perform the whole play ignoring the costume inconsistencies.
The whole cast and backstage staff should pretend to go along with it until opening night, and then on opening night as the curtains open, they make a short statement about the injustice then walk off stage and go home.
Alternatively, the cast should covertly learn the role of an opposite gender cast member. Then on opening night, the cast members assume their opposite role and perform the whole play ignoring the costume inconsistencies.
I’m guessing the drama teacher will not allow any of that in order to keep their job.
Who says the kids have to tell the drama teacher?