Jo was in a bind. It was ten minutes until the end of class, but she had to go bad. She had been holding it for the last fifteen minutes and she couldn't hold on much longer. But every time she asked to be excused, all she got in reply was a glare and a firm 'no.'
To her credit, Jo made it to the end of class. As soon as the bell rang, though, she bolted down the hall and into the girls' restroom. Unfortunately, she had just made it inside the door when the flood gates broke and her panties were soaked. She flopped down in a stall and sniffled, but then she felt the tingle again and her panties became dry. Also, she felt a training bra materialize on her, and her pants shifted into a skirt.
Hiking up her skirt, Jo saw that her panties now had Ariel on them, and looked very juvenile! Curiously, Jo slipped a hand into her panties, to see if they were wet. She shivered as she brushed her slit, and soon found herself rubbing it slowly. But then she realized she was going to be late, and ran off to class.
"Ms. Shmo, you're late." Mrs. Wren stated to the class as Jo tried to slip in unseen.
"I know, ma'am. I'm sorry." Jo said meekly, slipping into her seat.
"Just don't let it happen again, okay, Joan?" Mrs. Wren smiled and started writing out some practice algebra problems on the board.
Jo never was good at math, so she found herself getting bored. Her mind began wandering as she day dreamed about, well, everything. Boys, girls, the latest bands, movies, the list went on... But soon, Jo snapped out of her reverie. She had to poop, badly.
"M-mrs. Wren?" Jo asked, raising her hand.
"Yes, Jo?"
"Can I be excused to the restroom, please?"
"You may, but be quick."
Jo got up and ran for the door, but her foot caught a book bag and she fell to her knees, the force catching her off guard and making her mess her pants. She knew someone saw her filled panties, because she heard laughter as she ran out of the class and to the bathroom.
When Jo stopped once getting there, though, she didn't feel the heavy load. Instead, she felt like her undies had grown thicking. Lifting her skirt, she saw that she was now wearing training pants. "That's weird, why am I wearing pull-ups? I was wearing panties this morning."
The rest of Jo's day went...