I taught 10+ people. Back then, just last year, the cube craze in our school has just started, and only 2-3 people know how to solve the cube (myself included). Suddenly, the craze spread throughout the school, and many of my classmates wanted to learn. In the next few months, we have almost a quarter of the batch know how to solve the cube and fast, talented people started appearing among the newbies and also taught people at our school (including the freshmen).
Also, as a tradition in our school, there is a Rubik's Cube competition at every Science and Mathematics Fair. It's just for fun, and the winner gets 500 pesos (about $10).
Sadly, this year, we have to use the Math Club's cubes and the cubes aren't broken in and lubed. Surprisingly, the winner won with a 21.xx lucky single. I had a 49.xx single (slow turning, <2tps, hard to do M's, I used Roux) Averages do not determine the winner because it takes up too much time. Still, the event is fun.
We have actually went far into teaching each other; <10 of us have 25.xx average, 3 have sub-25 average, but only 1 is sub-20. Only me uses Roux, 3 use Petrus (1 of them uses MGLS), 1 uses ZZ, and the rest of us -- Fridrich.
Only one has a WCA profile.