Well, it did appear that the chap was off sick...
I had a 14/15 yr old at the same school berate me for dismissing a ckass with "Ladies and gentlemen - you may go."
"That's sexist! There might be someone in here who doesn't identify as male or female..."
"I checked the electronic register at the beginning of the period and everyone in the class is listed as male or female: no one in the class is listed as being binary or any other gender."
That seemed to placate him, but as they started to leave, an argument ensued between him and one of the girls. "What are ye goin on aboot? There are only two genders!"
I recall that he tried to insist that there were 64. The other kids weren't buying it.