Holy shit, did I laugh at the O.P. A good laugh, I’d not thought of this kind of thing in decades. Yes, I’m old.
In elementary school, kids keep their workbooks in their classroom. Carrying books was rare.
In Jr. High, now known as middle school, two HUGE things happened. You had to carry materials from class to class, and you hit puberty.
I got an erection on Tuesday, October 11th, 1975. I lost that erection somewhere in the morning of Friday, April 23rd, 1977. I kept my textbooks clamped against my hip bones, and crossing my pelvic extremeties for reasons that have NOTHING whatsoever to do with hi[ structure or balance points.
I’d always believed that the young ladies populating both the daytime hallways and nighttime fantasies of my Jr. High School years suffered the same self-consciousness, and held their school books and binders to their bosoms for the same reason.
And, I prefer to believe that still.