My time as a kid was before Legos, but we had Lincoln Logs and Erector Sets, and I spent many hours playing with them, building cabins and machines and whatnot. I've always been sort of a tinkerer, and had my bicycle apart several times, including taking apart the rear hub with its coaster brake. The odd thing about coaster brakes is that they work on the same principle as motorcycle clutches. Later, when I had cars, many of which didn't run for much of the time I had them, I had the engines out and all apart.
Regarding spatial thinking, I've always had a fondness for maps, and remember sending away to the U.S. Geological Survey office in Denver for 15' topo maps. I still have about 40 to 50 topo maps of the areas where I go hiking, the Olympics and Cascades in my home state, plus a few in the Sierra Nevada. If you know how to read a topo map, you have a good idea of the terrain it represents.