I'm an English proffie, but one with an historical bent, which I'm able to indulge in my one literature class this semester. The class includes among its goals fostering students' ability to make connections between literary texts and their historical contexts, so we're looking for additional documents that provide contextual information for the literary texts we're reading. Overall, it's going pretty well, but I'm learning that some of my students have very little sense of time (and/or they don't want to admit to having a sense of time, because that would require them to pursue their research beyond the first vaguely-related source they locate). So far, I've learned the following interesting facts:
--Years beginning with 19 can be classified as belonging to the 18th century (even though we're currently studying the 19th century, so I'm not sure why this classification would be useful or desirable). I'm used to the starts with 19=19th century mistake (in fact, it took me a while -- as in part of elementary school -- to stop making it myself, and a few more years after that to stop having to consciously think it through each time), but I'm not sure where this one came from.
--Someone who published his memoir in the early 21st century can be argued to have firsthand knowledge of the mid-19th century (he lived a long life, but not that long).
--Nobody knows how to read roman numerals any more (and apparently it's too hard to learn -- even though I'm pretty sure I did so by third grade -- or to google).
I'm getting the impression that a substantial proportion of the class considers anytime before they were born (mostly in the very late 20th century) a vast, indistinguishable wasteland of "back in the day," with little differentiation between the mid-20th century, the 18th century, and when dinosaurs roamed the earth. At least I'm pretty sure that most of them don't believe that dinosaurs roamed the earth 6,000 years ago, but that's not a great deal of comfort when I'm trying to get them to consider how much change 25 or 50 years can bring, and they're blithely treating texts created nearly 100 years apart as more or less contemporaneous.
I suppose if my students advance a bit in their understanding of any of the above subjects, they will, in fact, have learned something useful in the gen ed class they're taking from me, but I really didn't expect to be explaining any of this to college students (or to find them apparently unembarrassed at not knowing it already).