I LOVED THESE. Those silly rubber "Poppers" that you'd flip inside out, place on a table, and watch it scare the crap out of you when it finally popped and righted itself. Admit it, you flinched every single time.
The classroom overhead projector. Some of these were still in use last school year when I retired from the teaching profession. I had only had mine out of the classroom for a year, when I went exclusively with the smartboard and the E.