For about 45 seconds, the whole class is awkwardly silent. "C'mon, anyone?" Ms Tomlin asks teasingly. "Don't be shy." Finally, she declares, "Well, I didn't want to do this, but I guess you all forced my hand." She waved her hands in some kind of magical gesture, and all of a sudden, every student in class, you included, was naked.
A moment later, you felt a weird twinge run through you. You looked at the girl next to you, and could tell she had experienced a similar feeling. "OK, try to focus on the instincts you get from YOUR body, not the bodies of the people around you," Ms Tomlin called out. Doing so, you noticed the intense tension in your chest. "Boys, don't feel awkward about feeling pleasure from places you haven't before. Girls, feel free to enjoy how the strength flowing into your muscles feels." Your nipples had rapidly become twice the size they had been, and they felt about ten times more sensitive. "Girls, have you felt your slit seal up and expand into a scrotum yet? Boys, have your testicles moved inside you yet?" As she says that, you wince as you feel your own do that. You kinda want to touch yourself, but your penis feels weirdly extraneous to your body.
"We're approaching the crossover point now," Ms Tomlin says. "That means the people who were boys are almost closer to girls than boys, and the people who were girls are nearly closer to boys than girls. Some of you might be feeling disconnected from how your body is changing, and others might be really enjoying the feeling. Either way is fine! And don't worry, it's not permanent!" You're definitely one of the latter kinds of people. You stifle a moan as your breasts start forming, and smile as you look over and notice the girl next to you barely has them, and that her penis is already longer than yours.
"You might have noticed your sexual feelings changing," Ms Tomlin pipes up again. "For girls, you'll instinctively want to put your new penis inside things; for boys, you're starting to need your body filled up. You don't need to feel weird about these feelings, they just come with having the type of body you're getting." She's not kidding- your body doesn't have a slit quite yet, but you're definitely aching to take something inside you. That girl next to you doesn't seem to be quite ready to fuck someone yet either, at least- her cock is about 4 inches long, though it's growing longer.
Soon after, you finally feel your labial lips open, and your pussy is wet as fuck inside. Looking around, you recognize how the boys have changed now they're girls, and how the girls look different as boys. Looking down at your body, you see a girl, and you realize your mind isn't disconnected from that one bit.
"OK, so most of your changes should have finished now," Ms Tomlin says. "You might be finding your new bodies weird or overwhelming, so for the next 10 minutes, if any of you want to let those feelings out by masturbating or having sex, feel free to."