In highschool (8th grade), together with one of my best friends, I tought a computer science class (which up til then consisted of learning about PC-Shell). We prepared some texts and exercices on batch files. After that year, I lost track of him (I forgot why but I think it had to do with me flunking and changing schools). A few years later, in Uni, I bumped into him again. He , obviously, was a few years ahead of me and we only occasionally met in the hallways. After he graduated, I spent a few more years in Uni. For some reason, just now, he joined an IRC channel and we got talking again.
It's fun meeting old friends and catching up.