I teach high school and i keep in touch with several former students and am welcome contact with them. In the matter of fact in August I am going to social distancing baby shower of a former student. But those are students I keep in touch.

If I don’t keep in touch and run into them I am happy to chat and catch up. But if after running into me and not acknowledging recognizing me, they looked up my house address and sent me cards, I’d be taken aback. I’d be like what’s up with that. Its kind of creepy.

If they asked for my email address and I provided it, that would be fine. Not looking me up after the fact. What for

I’d not be sending cards unless there is some special reason

PS to clarify I spend at least 4 years and up to 6 years with my students as a teacher and case manager so keeping in touch and remembering them isn’t an issue. If I taught a student one single course for one semester, I probably wouldn’t remember them and even if I did, postcards 20 years later would be weird to say the least