Yup, Tis what I'm waiting for ??? . I completely disassembled (down to circuit boards) a TI-99/4A when I was 4, It worked until I was in my teens.
When I was combining tools this weekend I found an oil filter strap wrench that looked like it would fit the SV, so I tested it out (too big), and less than 5 min later he got it out of the drawer, and was under the bike trying it for himself.
I've got a 1x3 with a few wire nails started, and usually give that to him with a 6oz ball-pien, he's starting to hit the nails, and hasn't smashed any fingers. It usually keeps him busy for 15min or so.