Teaching font can be an incredibly frustrating subject in design because it is tedious, and there are so many factors. Students need to practice intentionality, a skill most teenagers try very hard to avoid.
So to get them ready for the "big" font assignment I start with two mini lessons that help Let them practice these things in Formative assessments.
A couple videos I like for getting the message across.
Mini assignment 1: Words on Pictures (dumb name bear with me)
This assignment has a very fast critique at the end of the assignment, I just read through all the images and decided if they were successful or not matching the text to the quote and the image. Some of them are pretty funny, but they soon realize that many of them didn't quite meet the requirements, so as a group we talk about the common problems we see and what we could do to fix them.
Mini Assignment 2: The calligraphr lesson (Not spelled incorrectly)
Calligraphr is one of my favorite tools I found on the internet as of late and it beautifully and immediately shows students the anatomy of font. you can choose your template and what letters you want included you print your template and then you have the students make their very own font. It can be decorative or I also just let them make a font of their own handwriting.
These two lessons are quick and easy, keep them busy, and show instant results when preparing them for the final font design. They create a new font with a clear purpose and then use it in a scenario.