Figured out the gist of the gender swapping bit: you'll need to take a tumble in flying class and be subsequently brought to the medical wing. This seems to have a random chance of triggering. It also needs to be the friday class, not training on your off time solo. Additionally, the player needs to be saddled with high arousal for the event to continue on.
Some time later at the same location (where you were healing up before) you will encounter another npc , which then points the way to the next chunk of the quest which will involve the library and talking to the charm or potion teacher. You will also need a fairly high score in either of these to proceed. After that it's just a matter of hitting the hallway in the afternoon or so and finding an abandoned classroom.
There's a fun bit of dialog with every character regarding the change, ranging from verbose to simple. After that it seems to pretty much be the same story and flow of the chosen gender.