Maybe I was an unusual kid, but the idea would have never occurred to me, had I not been regularly confronted with discussions of masturbation.
At our home study of the Youth book, which I think should be grounds for a CPS Hotline call, there was discussion of it IIRC.
Then there was some dumb article about not sleeping with tight-fitting pajamas, not lingering in the shower, and doing things such as emptying the trash if you felt the urge.
The persistent use of "self-abuse" to describe masturbation really made me believe there was no difference between the two. Maybe I was just naive but that's what I actually believed.
I assume it had different effects on others. Did it give you the idea to do it? Or did you feel traumatized about these private/adult topics being discussed in the hall? Embarrassed?