if you punish a boy to wear a skirt as punishment
I would never punish a boy in a skirt as it somehow implies that a skirt is a lesser garment. A skirt is actually very comfortable and practical for a boy. I was regularly put in a skirt when I grew up but never as a punishment. When I got home from school I changed out of my shorts and popped on a grey skirt for my home work. But the thing is when given the chance to put my shorts back on I preferred to keep my skirt on.
This was a frequent occurrence also worn with white pelerine socks and Mary Jane sandals.