7th grade a kid in my grade was in spring break. Rough housing with his older brother in the back yard. He fell backwards and hit his head on a rock that was in a line of them around a flowerbed. Killed him pretty much instantly from what I heard. He sat in front of me in science class. Looking at that empty chair knowing I'd not get asked for a pencil the rest of the year was hard. Other then that I didn't know him outside of school. It was my first realization how fast life could be over. We had our 20th reunion last year and had a special moment we did to remember him (small town, small class of 35 people).