Jake found himself staring at a classroom filled with 9 year-olds. They grinned and a couple laughed. This was a 3rd-grade class! Then he realized he was the only one wearing gym clothes. The teacher, a friendly-looking woman, shook her head. "I thought you were going to the bathroom, Jake. You certainly don't need to change clothes for recess! That's middle school." She looked at the clock and sighed. "Oh, well. Go ahead and play outside, and change back when you come back in."
Just then, the bell rang and the class surged for the exit to the playground. Jake was still confused - he had shrunk again, apparently 9 years old to match his new classmates. And the teacher knew his name, so he belonged here. A couple of boys came over - Terry and Mikey, his best friends. His what? Jake knew these boys as soon as he saw them, and also 'knew' they had been friends since kindergarten. Mikey grinned. "You peed yourself again, didn't you? Where did you get the clean clothes, though?"
Terry tugged at him. "Come on! Let's go play while we can!"