I also feel it's necessary to help children avoid the consumption trap. But why not start with a low-end embedded system? It would be easier and cheaper to source, program and take home. Plus: blinkenlights.
I'll admit, the project started out as a strange search to find the latest Linux distro that would run reasonably on a 486. That's why the Slack 11 hard drive image is provided - it's the result of my search. However, hearing a floppy drive churn and realizing a boot loader is short made the conjunction in my head click: OMG my daughters need to understand this!
I also admit that Slack 11 is my own personal opinion given hardware constraints. Others have performed a similar search.
Yeah started on Slackware 3 on 80386s myself. The package installation process was very good for stimulating curiosity for new 'nixers about system packages. I particularly loved seeing bison: a parser generator in the style of yacc pop up. Cracked me up every time!
I also admit that Slack 11 is my own personal opinion given hardware constraints. Others have performed a similar search.