Well, I have dermotillomania, meaning I compulsively pick at my skin. So, the majority of the scars I have are from that. One on my left wrist, where I literally dissected a freckle, and kept picking off the scab that formed. One on the inside of my right elbow just from repeated picking. One on my left shin and right ankle from a mishap of shaving, and that I kept picking at... et cetera...
My favorites? There is this one on my right palm from where I accidentally stabbed myself with a pencil in fourth grade. The tip of the lead broke off, and my skin healed over it, so I literally had graphite inside my hand. Two years later, my dad spazzed out about it and made a doctor "attempt" to remove it. They literally dissected my hand, and afterward... they didn't even remove all of the graphite. So now I have a scar there as well as graphite. Fun, right?
Another is on the outside of my left forearm, from a staph infection I got in sixth grade. I actually remember... I was fighting Dongorongo from Phantom Hourglass when my sister pointed that fugly sore out to me. But, yeah. It's not as visible as it used to be, but there is a round scar from where that was.