"Well then, let's build a tower and drop stuff off it!" If he stacks up a bunch of blocks of dirt and rock, can he make a story or two of climbable freestanding staircase? Being able to chop the supports out from under a block and reuse them should help there.

He can definitely do that!

{wow! you can go up so high!}

"Yup! . . . Possibly I should be figuring out some sort of railings." If he makes the staircase three blocks wide with the outer two being elevated by a block relative to the inner one, it should be much harder to fall out but not any harder to drop things. It's a bit slower, but it doesn't take that long to get to a good dropping-things height. "Okay, want to climb it and see if heavier objects and lighter objects fall at the same speed?"

Bounce bounce. {yeah!!}

"Great, let's get some things to drop!" He grabs a minified block of wood, an apple, and two sheets of paper (one to fold up small) and gestures an offer to carry the forest spirit up the stairs since their steps are kind of large even for a human.

The forest spirit will happily be a Shoulder Friend for this experiment.

Then once Bruce has demonstrated counting at a steady pace, they can drop stuff off their non-leaning tower! Just like Galileo except much better off in a lot of ways.

The apple and the sheets of paper fall in just about the expected way.

The minified block of wood seems to have an abnormally low terminal velocity, and drifts to the ground only slightly faster than the flat sheet of paper.

"Whoa," he says, watching it fall. "That was an unexpected result! Did you expect that result? I should have asked you what results you expected before I dropped anything but I got overexcited and forgot." Bruce is so hype about getting an unexpected result.

{didn't really expect things,} the forest spirit confesses. {but if i expected things it wasn't that!}

"What do you think will happen if I attach a piece of paper to the wood block and then drop them both?"

The spirit considers. {attach how?}

"Well, I don't have any glue or string, so the first thing I'll try is rolling the wood up in the paper and folding the ends, like I'm wrapping a--okay there's no way you've heard of Christmas presents but my point stands."

The forest spirit spends a moment picturing this, then nod-bobs. {maybe will fall like paper! maybe will fall like wood! maybe will do something different!}

"That's roughly my hypothesis space too. Now we try it and find out!" He makes a quick trip back to ground level to retrieve the materials and then does so.

The paper-wrapped wood falls like wood.

"Okay, so we know that blocks can hang in midair, and the wood is sort of more like a block than the piece of paper is. I wonder if there's a weight limit to what it can slow down, or if it would fall exactly the same if there was something really heavy tied to it. I don't have anything heavy and easily attachable, though."

Thinking, thinking...

{stand on ground, hold wood, jump up?}

"Yeah, good idea. I don't think anything will happen because it moved normally while I was walking around with it, but you gotta try it to find out for sure." He goes down the stairs and holds up the wood and jumps. Off the last step of the stairs, to get that bit more airtime.

If the block is lagging at all as he drops, it's too subtly to notice. Or, on the other hand, Bruce might be falling weirdly right along with it. How familiar is he with what it's like to jump off a two-foot block?

Not super familiar, but he can jump a bunch of times with the wood and a bunch of times without and then if the forest spirit is up for it they can do the same thing.

The forest spirit is up for it!

There doesn't seem to be a difference between the way they fall while holding the wood and the way they fall while not holding the wood, or between the way Bruce falls and the way the forest spirit falls.

"Okay, so either we're both too heavy for the wood to hold us up noticeably or we're in a different . . . category . . . than the piece of paper. I'm going to try dropping more things and see if that helps me get a sense of what the categories are." Back up the stairs again to drop: a wood beam, his otherwise useless dorm key, and a stone block (preceded by "watch out, this could make quite the thud if it doesn't hang in midair").

It turns out not to be possible to get a stone block into a droppable state. It's not obvious how to do it with the wood beam either, for that matter. They only want to come into existence attached to things.

That continues to be weird a phenomenon he doesn't understand yet, but okay. Do the apple and his dorm key at least land simultaneously if he drops them simultaneously?