I actually had an entire girl's PE class stomp through the boy's locker an shower room while I was bathing post weightlifting class.
It was interesting lol.
No idea how the teacher didn't think to check to see if anyone was still in there. But I hear voices and footsteps and step partway out of the shower room and there's a passle of girls just walking and talking.
As they notice me poking my head out, one of them squealed a little, so I jumped back and grabbed my junk lol.
This did not stop most of them from going right on by though. They went to the "ball pit" aka the storage room where gear was kept, got their basketballs and then went back past again. A few whistles, some laughter, and a greeting from a friend were all that really reacted much tbh.