Assume that you can categorize people relatively well, perhaps not perfectly every time the first time, but well enough. You can change their type later on if you learn more about them or if someone else convinces you that you've typed them wrong.
After that, what can you do now that you know their types? I'm thinking of a few things.
1. Design a school curriculum that supports each of the types' strengths and weaknesses
2. Socionics dating (already being done in Russia, but the English website doesn't seem very active)
3. Design groups of people who must cooperate with each other (already being done in Russia)
4. Communication, persuasion, diplomacy, conflict negotiations - how do you talk to someone or persuade somebody to do something if they think differently than you do and value different things? Which beliefs and customs result from socionic quadra values, and which ones don't necessarily? For instance, religious believers and atheists exist in all quadras. So that is something that doesn't necessarily depend on quadra values, but it can be connected with them. How can you change someone's mind about something? How can you persuade someone to do something, believe something, or value something? How can you use socionics knowledge to help you do this?
5. Criminal profiling - guess who a serial killer is, for instance, based on the style of the crime and the letters they've written to police and the media.
I would like to see a teaching curriculum that teaches something to all eight functions without neglecting or disvaluing any of them. You wouldn't even necessarily have to know someone's type before putting them into the school. You could find out what their type is by teaching something to each of the functions and then getting feedback from the students about which classes they liked and disliked the most.
How do the functions manifest in existing public school classes?
(edit: I should probably call them 'information aspects' here instead of 'functions.' I'm talking about a school that teaches something that has to do with each information aspect.)
life skills (or whatever it's called depending on where you live)
shop class (woodworking, etc)
other (I can't recall all of the classes that exist.)
Also, what is the purpose of a school? Different answers to that question might depend on quadra values. I always felt as though school should teach me something that would be profitable in the real world, some kind of job skill, and I felt frustrated with school because I couldn't see how a lot of the classes had any connection to the job world. I felt the same way in college (I dropped out of college). But some people feel that the most important job of a school is to pass along society's values and traditions, for instance, or, to show students broad areas of knowledge that they might not look for on their own.
I am mostly interested in the idea of socionic schools and also the idea of using socionics for persuasion and communication, but I'm also wondering about other applications and uses of socionics. We spend a lot of time struggling to correctly classify people, but after that, what do we do with that knowledge?