Of course, I can only speak from my experience.
I had a book published by the University I studied in, called 30 centuries of types and letters (30 siglos de tipos y letras)
Studying the history of the writing, from the ancient cultures, Greeks Romans, "dark ages" etc. And then "Post Gutenberg" type design! It was an eye opening.
Each typeface had a meaning, a purpose, a reason why it was used and invented. Technical challenges, historical reasons, political reasons, commercial or ideological reasons.
This kind of knowledge is one of the best you can share IMHO. (this is not only in college academic realm, I had discussed this to my 15-year-old son and it is interesting and good general culture stuff too)
For one class only choose a couple of examples that have any of those. Technical, political, commercial, ideological reasons.
One exquisite field of graphic design is calligraphy and text only design.
Explore Text only design! Explore, explore, explore!
One interesting example for non-achademic students is to grab a poster, for example, a futuristic one, and change the font for one that would not reflect the thematic, for example using a "textura" (medieval font).
4. Make them design their own typeface!
What do they want to say? Regardless of the language used in the writing?
A good font can say stuff regardless it is on Italian, latin or english... Explore that.
But this exercise can go beyond a computer. They can design the typo using rocks, cardboard or paper, yarn, water... (They can take a picture in this case, or use watercolor)
Using different mediums gives different results, this will render the technical difficulty evident.
One interesting option is to use paint programs. Explore for example this ones: https://www.escapemotions.com/experiments/rebelle/index.php
5. Word to font!
For homework, not for class. Grab only one word. It can be a subject, a concept.
a. Choose a font. Black and white only.
b. Then choose a color.
c. Then choose a texture, etc. Play with that.
This is a homework project so they face themselves to this decisions. In class, they must show the printed result and compare to the results of the rest of the classmates.
I must say I loved this question...