I agree more with "willy" relation of a group physical where boys are naked in front of the girls classmates and not them.
I like the idea of boys being photographed in the nude while the girls could watch and then the boys went out of the gym when it was the turn of the girls.
I like double standard situations more exciting for me
At the beginning, boys could be in jockstraps showing their butts to all girls classmates first undressed in panties and bras and then being in gowns while the boys will stay in just jockstraps until instructed to remove them to be stark naked.
All took place in a large gym with several stations for examinations and calisthenic exercices
All the medical persons would be females, a lot of nurses mainly young ones and also doctors because they were the only ones interested by that kind of routine examination which were not much paid.
and same for the Pe teachers;, all females, because it was considered indecent and unfair to let male Pe teachers see girl's students undressed even in panties and bras or wearing gowns while the reverse was not all an issue.
Some female secretaries were also required to check identity and to fill an administrative forms about each student and also to check and fill medical forms such as vaccinations records and so on.
All were volonteers to be present in the gym for all a morning.