When I was in 3rd or 4th grade, we were loaded on a bus and taken to the near-by university, where we saw *gasp* a laser (looked like a long machine gun) and *gasp* a gigantic IBM computer that read punch cards. It was cutting-edge technology & we were supposed to be highly impressed by this glimpse of the future! 
They turned the laser on & showed us the pretty red light. I don't remember them telling us about any practical application for this light, though. I'm not sure they had any back then. They were just a university with a laser, which was Big Stuff & a reason to bus the kiddies over to see it.
My favorite part of the trip was being allowed to take home a punch card to show to my parents. Woohoo. 