"We do have cake! Earth is a lot of different ways in different places, but I live in a really good one. It's a city called Cambridge, and I live with a bunch of people who are all learning all the science we can. I'm mostly learning about how human bodies work so I can discover new ways to make humans healthier."

Happybounce. "That sounds like a good thing to learn! I like learning things."

"Learning things is great! What have you been learning lately? Do Zoombinis go to school?"

"Older kids have school sometimes! I was helping make the boat this week so I learned things about that. Sewing is hard!"

"Sewing gets easier with practice. Not that I know much more than how to put buttons on things. How do you hold the needle, by the way? I use my hands for stuff like that."

"Oh!" they say, peering curiously at Bruce's hands. "That's not how we hold things!"

"Would you mind showing me how you hold things? I'm sure it'll be obvious once I've seen it but I'm having trouble imagining it."

Kwispafa looks around for loose objects and can't immediately find anything; the grownups are keeping the deck pretty tidy.

Bruce fishes his student ID out of his pocket and holds it out.

Kwispafa nudges it, then picks it up. They seem to be holding it with the side of their face; it's hard to describe but looks pretty straightforward to accomplish if your face happens to work like that, which human faces definitely don't. Then they flip it neatly up to the top of their head - "see, and this is how we carry things" - and tip it off again and catch it and hold it out to Bruce.

"Wow, okay! I can't at all do that, that's neat," Bruce says, taking the card back and pocketing it. He makes a frankly bizzare and ridiculous facial expression trying to do that and confirms that he super cannot.

Kwispafa giggles at him.

Bruce giggles at himself. "So what sort of things have Zoombinis invented? Humans have invented a lot of stuff and I'm curious if we got the same things in the same order."

"Boats! Cake! Potato fries! Wheelbarrows!" says Kwispafa.

"We have all of those! Do you have cars? Hot air balloons? Microwave ovens? The light bulb?" They clearly have something powering their propellers, so it seems like a decent bet that they have electricity.

"What's a hot air balloon? What's a microwave oven? I know what a car is, it's a part of a train! And lightbulbs are part of lamps!"

They have trains! Trains are great. "Hot air balloons are balloons--big bags of cloth--with baskets hanging under them, and you light a fire at the bottom of the balloon, and it heats up the air in the balloon which makes it expand, and that makes the balloonful of air weight less than the air around it so it floats up into the sky! Microwaves are boxes that make an invisible kind of light that heats things up, like how sunlight feels warm but moreso, and you can use them to heat up food."

"Wooow! I don't think we have those things at all!"

"My world has a lot of cool things! Most of them use electricity; I'm guessing you have that and the propeller folks use it to turn their propellers but I guess you could be using something else we haven't invented."

"I don't really know how propellers work," Kwispafa admits. "Lightbulbs use electricity though!"

He is not going to ask to take apart a propeller and see how it works. He is not going to do that. He is going to say, "I guess I'll have to ask an adult with a propeller at some point. Do you know if you've invented the steam engine? In my world we got that before electricity."

"Yeah! Trains use those."

"Nice, so did the ones in my world for a while. It's too bad I don't get to see your cities and all the cool things you've built. But maybe I'll get to see you build new ones!"

Happybounce. "We're gonna build new ones in the lands of logic and it's gonna be great!! I wanna help my parents design our house! It's gonna be taller than you!"

"Is it going to have multiple floors? Do you use ramps to get from one floor to the next?" Sure, those wheels can apparently climb a rope, and isn't that embarrassing when he cannot climb a rope even a little bit, but stairs still don't sound optimal.