“poppi. can i go up on the flat roof and throw down this parachute i made? i want to test how many marbles i put in cup before it doesn’t float anymore.”

of course! because even if he doesn’t know he’s empirically testing the physics of free fall and drag with parachutes, i can still understand the fun of standing on the edge of a roof and throwing stuff off the edge.

and, amusingly, i remember being his very age and wondering how many garbage bags i would have to put together to safely carry me down from the top of a tree.

it floats!

he could put a few marbles in the cup before it became too heavy for the size of the parachute. it’ll be interesting to see if he figures out how to plot various surface areas against max weight carried.