I don’t know if this counts as a childhood memory, because I was thirteen when it happened. But whatever.
I was in this musical group, that did musical reviews, which are basically shows consisting of songs from various musicals. The week before the show was tech week, so I would show up at the theater every evening after school, and stay for a few hours rehearsing. I had a ton of homework, and I had to get it done, show or not, so I brought it to rehearsal with me.
I was taking geometry that year, and as such had this huge TI-83 graphing calculator. At the beginning of one rehearsal, I was stretching with my foot up on the edge of the stage, while also doing my geometry work, my books and calculator on the stage as well. As I was stretching, my foot knocked my calculator off the stage, and right onto my other foot. It hurt like hell, but whatever, I was fine.
Until the next morning. My sad little pinky toe was all bruised and swollen, and after prodding it painfully, my mother declared it broken. Unfortunately, since it was my pinky toe, all I could do was tape it to my next toe and keep walking and dancing on it. Which sucked ass.
So yeah, the only broken bone I’ve ever had in my life was because I’m a nerd.