Electric Box is a very smart puzzle game that I had the opportunity to playtest before it was finished. In fact, the creator added Level Editor because I suggested it!
The game presents you with a partially completed circuit, an on/off switch, and a target. You also have an array of whimsical objects at your disposal that you can use to complete the circuit. For instance, in the first level you have a light-bulb and a solar panel that you can use to transfer the electricity from one. Other gadgets include lasers, mirrors, steam kettles, and water wheels! Some levels even require you to use objects to rearrange other objects, meaning you have to think ahead, or succeed by experimentation.
While Electric Box isn't explicitly educational, it will certainly give you some good mental exercise. You could also look at it as a model for a fun educational game about electrical engineering, or digital logic.
I actually thought circuit diagrams in physics class were very interesting, likewise logic circuits in my computer science classes. I would really like to see someone do an educational game that simulated those kinds of elements. If anyone out there ever does, I advise looking to "Electric Box" for inspiration. It gets the game elements, difficulty progression, and tutorials exactly right.
I have designed a level myself using the level editor. It has 2 ways to beat it. Here's the level code.