Hah, that's awesome- if anyone knows of it, would love to know the name!
I'm definitely familiar with tutorials for programming languages/tools/environments using the medium itself, as you just described - but have never seen anything in game form. Further examples appreciated!
I'm not sure about on the Mac, but that sounds like the MS Works 1.0 tutorial for the database component. The scenario was for a ski field where there had been a murder, and you had to whittle down the suspects based on the clues found.
It started out like a game. There was a grey background, then footsteps appeared, marching across the screen to gravel-crunch noises. And the queries were for guests in a hotel, IIRC.
I'm definitely familiar with tutorials for programming languages/tools/environments using the medium itself, as you just described - but have never seen anything in game form. Further examples appreciated!