I liked the trains, the chemistry sets and the erector sets.
I still have my American Flyer Train set that my late parent bought for me in 1957. I am working on a layout, cleaning rusted track, and getting ready to set it up.
I also had an AC Gilbert Chemistry set-producing kitty gas was my favorite experiment.
About 10 years ago, I purchased an Erector set-that is my next hobby after I get the trains going.