I should dig through my cabinets and boxes and locate all the obsolete software that I have. Surely there is somewhere that can use it now that my kids have outgrown it more than 20 years ago.

I used my old 128k/512k Mac to teach typing and foster artistic skills with MacWrite and MacPaint and an old 386 pc, probably an Epson if I remember right, to set them up with age-appropriate skills games.

There is no substitute though for hands-on learning using manipulatives like puzzles, building blocks, etc. These teach different skills that are critical to gaining an understanding of how things work and in learning to visualize unseen parts of mechanical devices and mechanisms. Understanding physics is aided by assembling various parts large and small, heavy and light together and trying to build a working contraption that doesn't fling parts everywhere when you try to roll it across the floor. Balance and the effects of asymmetry are easier taught with real objects than with computer displays.