Need Some Inspiration

A long time ago, 3M Learning produced a series of interactive CD-ROMs for PBS' "Newton's Apple" program, titled "What's The Secret?" Once of the interactive exercises was titled "Why Does Glue Stick?" The goal was to, using the correct type of glue, attach objects to each other to the point you had a "bridge" from one side of the screen to the other. A helpful elephant would test your glue choices and either wait for the next object to appear for you to glue, or fall (fortunately not to its death). It was a great way to learn how different adhesives interacted with different materials, in a fun, non-destructive environment.

Maybe you could do something similar, by presenting the learner with different surfaces and different types of stains, and then letting the learner pick the cleaning product to see if it cleans (with accurate, and possibly whimsical, results).