You have got to be kidding me. It's not "outrageous behavior?"
Are you telling us that teachers -- be they neophytes or veteran -- need to be told not to induce children to take off their clothes in class as part of an exercise?
Where in heck are you from where adults that ask that unrelated teenage girls take off their clothes for fun aren't suspected of doing so for prurient interests? Why should parents be satisfied with less than termination of not one, not two, but three people entrusted with the care and instruction of impressionable pubescent teenage girls who don't even have the common sense necessary to know this was a ridiculous idea?
Worst of all, you're blaming the girls for taking it "too far." "Too far" for what? Isn't the idea of "strip ANYTHING" to potentially strip completely to the delight and amusement of all participants? Have you forgotten whose idea it was for the girls to strip in the first place?
Have you been a teacher so long you have forgotten what parents expect of teachers? Have you been working in the cannery so long you can't recognize when something smells fishy?
What is WRONG with you?
Did they? Read it again. What they said appears to be different from what was done. The debate is whether or not the result was what was intended.