When Jeff woke up... his room looked the same. He was still a guy and didn't know how to turn into a girl... or any of the other changes or implications something like this could have. So Jeff did what he always did, put his clothes on, and went downstairs where his mom who was still his mom making breakfast. His dad still had the stubble on his face, and very much the same man as he was before... and then there was his little sister who obviously wouldn't be learning how to turn into a guy anytime soon... hopefully.
Getting on the bus he took his seat and waited for-, and then at the next stop a girl sat next to him who had slightly long chestnut hair, wore a cute dress "Excuse me" Jeff said "My friend usually sits there." At which point Jeff noticed her backpack, some resemblances
Jeff's friend Kevin? giggled in her higher pitched tone "Yes, she does. My family's a little more old school and likes to have that sex class taught to us by the family. I'm just feeling it out." Jeff noted she had a decent rack, looked cute, and was a lot shorter than his guy self.
"Should I still call you Kevin?"
"Nah, like this I go by Keva" Keva said as she stared at Jeff's face seeing how well her friend was taking this shift. It's not like Keva was stuck in that form after all she could change back. School was mostly the same as Jeff looked around the courtyard. Familiar faces, some faces unfamiliar, a few faces semi-familiar who may have changed sex, and then came time for classes. The bigger one being the class on sex change.
It was a 30 student class where the teacher Ms. Krieger was going through the syllabus, finished up and said "Well with all that taken care of, it seems like some in our class has gotten a jumpstart we'll glance through a little history." She fired up a powerpoint and flashed through some points where Jeff got the main points. The exact moment when people figured out how to change sex was debated and there's some amount of speculation, but most people think it started early in human history. From then on people had the ability to change sex. Normally people changed sex for relatively short periods of time, or if there was some sort of need. Like for purposes of family bloodlines, arranged marriages, or if there were a large imbalance in natural sexes. Jeff raised his hand and then asked about gay people to which most of the class was confused and Ms. Krieger sighed. "Ok class, gay or lesbian or terms for people who like having sex with their partner while they are the same sex. It's a little depraved, but some people do it." and she gave Jeff a look as if to say "happy?" as if there were at least one student in the class who would ask that. Then she said "Class is about to end in a few minutes, but I would recommend reading your textbook about the energy points and mental imagery. Even if you accidentally do it all right sex changes takes 2-3 days to fully transition." Then the bell rang and class was dismissed.
Jeff was a little shocked that gay people were being described as a little depraved... then again if you can change your sex was there as much reason to be gay? He also wondered about trans-rates in this world, but if you can change your sex was being trans really an issue? He also thought that there'd be more people who stayed changed longer, but outside of maybe an exploration phase... you'd gravitate to one or the other wouldn't you, and most seemed to gravitate towards their birth sex. It felt a little shocking, but not at the same time. The world's different and something fantastical had happened, it just didn't affect most of it very much.