While I was a student in undergrad, we did an exercise where the instructor gave us two words (one word in a serif typeface and the other in a sans serif typeface), with each letter of the words printed on an individual sheet of paper. We were instructed to tack the sheets to the wall and kern the word by moving the sheets of paper. This exercise totally blew my mind and gave me an immediate understanding of kerning. Now that I’m on the other side, teaching students design, I’m doing the same exercise. It’s my favorite part of the course, and the students equally enjoy it. It’s really fun to watch them “get it.” From this point of the course on, bad kerning is unacceptable.