Kids were bored a lot. Get too bored and you find something to do. Draw, build with blocks.
I remember making a 'perfume' out of plant juice and flowers - absolutely vile, naturally, but that kept me going for hours.
I made 'pasties' out of leaves, stuffed them with seeds, flowers and whatnot, sealed them with pomegranate thorns, and pretended to cook them in a mud oven.
Caught bees in jars, then let them go.
Pressed flowers
Roller skated
Climbed trees and sat up there watching the neighbourhood for hours at a time.
Biked around the neighbourhood, I used to see how many time I could go around the block without using my hands, just steering using shifting balance.
I also read A LOT. But my DM wasn't keen on me reading as much as I did so I used to hide how often I read.
Made clothes for my dolls out of scrap fabric when my DM sewed. Had a treadle Singer sewing machine so I properly sewed but at a really slow, safe pace.
I used to pick the thorns off the rose bushes and stick them all over my face by licking the base.
Moving into early teens my cousin and I would buy coloured hair spray and cheap bright make up and turn ourselves into punks and roam the streets, stopping at McDs looking like absolute frights!!! Her DM actually took us there once, laughing at us hysterically the whole time.