The skill that lets someone teach their skills to others in an efficient way. While we encourage people to roleplay this out, it's actually not required. If neither the teacher or student find it interesting, you can just use the command and handwave it, though try not to do it in a way that would produce ridiculous results ("... and a day later after first touching a blade, he became a master swordsman.")
0: Anyone that uses, "well, actually" in a sentence, normally.
1: Teaching young students is way, way harder than it looks.
2: Can get across concepts to disinterested and frequently bored.
3: Can distill down the very complex to something reasonable and accessible.
4: Can guide the exceptionally, exasperatingly stupid to conclusions relatively quickly.
5: More than likely changes the lives of most people that meet them and have saccharine tributes after they die.
6: Could teach the world to sing in perfect harmony.