The sparkles land atop the two blond girls, and one of the pair grows taller and leaner, chest flattening out, hair shortening, while remaining blond, top turning into a letter jacket, blue jeans (was she wearing blue jeans a moment ago?) shift as her hips and legs change, and she becomes a blond guy, who looks athletic, if perhaps a bit feminine (or is it just that you know "he" was a "she" a moment ago?) As the sparkles fade, the scene blurs, and suddenly the two are in a passionate embrace, lips locked tightly together, looking practically ready to go at it on the hall floor.
"You see, my powers work on pretty much any aspect of sex, attraction, mating rituals, the act itself," the tiny woman explains, batting her eyes seductively at you. "High schools are among my favorite places-- even better than Nevada whorehouses! Hormones running high, the thrill of experimentation, lots of folks first time, or attempted first time. Boy and girl, boy and boy, girl and girl, or any mixture you can think of. Why, I remember once when the entire 4H Club--"
"W-wait!" you interrupt, not entirely certain you want to hear the 4H story this soon after your experience with your "math teacher". "So, what you are saying is that everyone now thinks that-- that what happened in there is normal, and that that guy has always been a guy? Any changes you make will be thought of as normal?"
"You're a bit slow, but you get there!" the sex fairy states approvingly. She smiles and looks around. "Now, what should I do next? Or should I just make a few changes on my own while you think it over?"