I was 13. We had a special assembly too, with all the teachers looking glum but not telling us anything until everyone was in place. Several girls started blubbing, and I wondered why - none of us had met him. An important occasion, yes, and sad for his family and in a general way, but they wept because it was presented as momentous, not for any real grief.
School dinner that day was cold ham and salad. They thought we needed something hot to sustain us, so we got brown beef gravy with it, drowning the salad.