[toto444]

I am writing one for Japanese (I was not aware of LLPSI when I started) and I use things that are common knowledge to a lot of people like set theory. I have used a few unusual things on the way.

I have recreated the UI of a fashion Ecommerce site such that the user is so familiar with the button labels ('buy', 'add to cart', 'recommended items') that they can easily guess their meanings.

I teach HTML using simple Japanese. I make use of the fact that "<span style="background-color: yellow;"> </span> " uses English words but is not English. That allows me to say things such as 'to change the background colour to yellow you can add this tag' without using English. It's definitely cheating but I have found that cheating is actually good practice when it comes to help people guess the meaning of words in a foreign language .