I got in a lucky accident once when I was in 7th grade. I was mountain biking in the woods down by the North River in Mass and I was going about 20-25 mph on loose rocks and dirt. Then all I remember is the ambulance. To this day I don't really remember walking back to my friends at the river and I don't remember ever falling. It was very scary. From that day on I always work a helmet. It's amazing what compressed styrofoam can do! I consider myself very lucky to be here today.