My first response to "let's do computers daddy" was to install a kids KDE Linux with some things like TuXPaint and whatever. But I noticed she really wanted to be doing what I was doing - typing. Also I had to launch everything. And it seemed inevitable that within minutes alone with the machine she'd accidentally get into desktop configuration and hide the task bar or something.

So then I thought, what about just Bash?

That didn't work so well either, and I ended up aliasing so many commands to simpler things - but it was a step in the right direction.

So now I just launch into a "kiosk mode shell" made in python that dispatches the commands we talk about together. We say... wouldn't it be cool if a computer could do this or that, and then I think about how to make that a single three letter command with a few options. I'd love it if she'd get into bash or programming properly as another commenter's kid did, but I won't push it, this is foundation work. There's every possibility she'll say "I'm bored with computers dad" and I'll just have to try not to be broken-hearted :) Perhaps the main aim is to cultivate a respect and healthy attitude for real computers, so tablets and phones seem like the toys they are.