I think a T-shirt is probably the most common apparel at any time for high school boys... picture day or no.
Heck, most kids seem to be fairly unaware of when picture day is... my son never knew. Though I will admit he can be gloriously unobservant.
Um... what?
Nobody gets taken by surprise... they send you home with an order form so your parents can choose what sort of photos they want (4x6, wallet size, etc...), what the background color will be, etc... and so that they can send you back to school with the money to pay for it.
This kid was a junior. He had already been through Picture Day 11 times before in his career as a student.
I just went through one of my high school year books.
The girls would get dressed like it was prom, and the guys would put some gel in their hair and wear something with a collar.
The number of students wearing t-shirts (without also wearing some sort of unbuttoned button-down collared shirt over it) is an extreme minority.
Of that group, the number of those t-shirts that had text on it was an extreme minority.
Of that group, the number of those whose t-shirts with text on it that was visible enough to actually be read was an extreme minority.
And that text might have been the clothing brand name, or in some cases the name of a local college..
None of the parents were silly enough to send their kids to school on picture day wearing a t-shirt with any kind of a message on it